from the New York Times

Bernie Williams closed his brown eyes and slowly bobbed his head while strumming his black guitar. When Williams is stressed, he finds comfort in his fingers gliding across those six strings and lets the music drown out troubles. At this moment, Williams was stressed and a little spooked, too.

A United States military officer had briefed Williams about the possible perils of traveling in Colombia. The officer said there were 14,000 guerrillas who wanted to overthrow the government, 12,000 paramilitary soldiers who wanted to quell them, and an uncertain number of Colombians who were ferocious about trampling anyone who interfered with their drug enterprises.

The officer calmly told Williams that he needed to address the darkest scenarios, so he also explained that there was the potential for a kidnapping. That is why the officer, who traveled with a 9-millimeter gun concealed in the waistband of his pants, promised he would cling to Williams like a sweaty T-shirt.

"You could die here," the officer told Williams. "My job is to make sure that doesn't happen."

Williams listened, absorbed and wondered. Did this make sense? Should he really be in Venezuela and Colombia as a new cultural ambassador for the United States across five hectic days? Was this plan rational after all?

Williams was a week away from spring training with the Yankees when he received the briefing in an airport lounge in Bogotá, Colombia, last Monday, and the same questions that friends had asked about his imposing baseball and music odyssey reverberated.

"Everyone I told said the same thing to me," Williams said. "They'd say, 'You're going to Colombia? Dude, what are you doing?' "

What Williams was doing became obvious and powerful as his journey to four cities in South America unfolded. Every time Williams was deeply affected by someone or something, something just as extraordinary happened a minute, an hour or a day later. Dude, Williams said he would tell his teammates when he reported to Tampa, Fla., this was a phenomenal experience.

"It changes how you look at life," Williams said. "This trip has been one thing after the other. Boom, boom, boom."

There was a 10-year-old boy in Caracas, Venezuela, who sneaked into a bathroom behind where Williams was doing a dugout interview, climbed a concrete wall and poked his head through an opening to pass Williams a jersey. Williams's smile showed that he appreciated the intrepidness.

There were a dozen 4- and 5-year-olds who wrestled with Williams on a second field in Caracas, swiped his sunglasses and modeled as miniature Bernies. Jolmón Avendano, who wore lamp black under his eyes, put his hands on Williams's chin and twisted Williams's face until it almost touched his. He wanted Williams to listen to him and him alone.

There were 30, 40 or maybe 50 little players scurrying from left to center to right field when Williams took batting practice with a Danny Tartabull bat in Cartagena, Colombia. Once Williams worked off three months of rust and belted a few homers over the 315-foot fence in right, a few boys scaled it, stood on crumbling white stairs and played the new position of right-field bleachers.

There was a smooth concert with a dozen college students at Universidad del Norte in this city, except for the two instances in which the lights in the auditorium went out. Williams was the musician everyone wanted to hear, but he tried lingering behind the band so as not to upstage them. He could not hide.

"As much as I was impacting them, it was even more for me," Williams said. "I was profoundly impacted by this experience. It was an eye-opener. It opened up the boundaries of the world I live in. The world I used to live in."

His world has changed now, Williams said, changed for the better, changed because he left the sheltered world of a successful athlete and visited people who knew of him and welcomed him.

The average Venezuelan makes about $3,600 a year. The average Colombian makes about $1,800. Williams, who was born in Puerto Rico and is a United States citizen, is in the final year of a seven-year, $87.5 million contract.

Even though Williams said that he was cognizant of the tense political situations in Colombia and Venezuela and the concerns that the United States has about both countries, he stressed that his journey was about influencing people. Williams said he did not consider the trip risky and never felt in danger. If anything, he said, he felt a 120-hour embrace.

"I was looking beyond the political picture to the people," Williams said. "It's different parts of the world and different cultures, but, in some ways, we are all similar. It's people."

When Brian Sexton, the senior adviser and special coordinator for culture of the United States State Department, contacted Williams about becoming an ambassador with CultureConnect, Williams was intrigued. It took about three years to coordinate the arrangements with the Yankees and for Williams to become the country's 12th cultural ambassador, joining luminaries like Yo-Yo Ma and Wynton Marsalis.

The program uses people in fields like music, art, literature and sports to enhance the understanding of America among young people in other counties. Williams agreed to a two-year commitment and is expected to make four trips during that period, all paid for by the United States. He and Sexton have discussed going to Japan and the Philippines after the coming season.

To Sexton, no trip is too far and no idea is too challenging. In his just-concluded trip, Williams squeezed in four baseball clinics; one concert; three exhausting workouts; dinner with Bill Brownfield, the United States ambassador to Venezuela; lunch with Colombian community leaders; an impromptu one-song performance using a borrowed guitar in Cartagena; and autographs for more than a thousand people. Easily.

He was too busy to call his wife, Waleska, until 11:30 p.m. on Valentine's Day, but made up for it by buying her emeralds. He lost his cellphone and was too occupied to cancel his service. He contracted a viral infection on his last day of the trip. He reminded hundreds of poor, baseball-obsessed children that baseball is a tremendous job, but an education is the safest route to success.

"It was," Sexton said, "Bernie's great adventure."

Williams felt like a C.I.A. officer after finishing two clinics in Caracas and flying to Bogotá with Sexton last Sunday. They were immediately greeted by Gustav Goger, an officer with the United States Embassy, who took their passports and luggage checks and told them their bags would be taken to the hotel. He then led them to an armored vehicle, engine running, that was parked near the tarmac and seemed more tank than Chevy Suburban. Goger explained that the 9,000-pound truck would withstand virtually any attack.

"If they shoot out the tires," Goger said, "we'll keep moving."

The next morning, Williams was as comfortable in the armored vehicle as he would be on his own couch. As Sexton and embassy officials joked about how much someone's boss would pay for ransom if they were kidnapped, Williams predicted what George Steinbrenner, the principal owner of the Yankees and ultimate boss, might do.

"George would say, 'Darn it, we should have signed Beltran,' " Williams said, a reference to the free-agent center fielder Carlos Beltran, who was expected to replace Williams in center field but instead signed with the Mets.

Williams was more serious during his clinics. He is content to blend in with the Yankees and would prefer it if 24 other players were the spokesmen, but he was assertive as an instructor. There was no blending in as Williams preached about baseball. This was his show.

When Williams arrived at Once de Noviembre Stadium in Cartagena in a three-car convoy, police officers in green uniforms held hands and rimmed the entrance to prevent fans from mobbing the vehicles.

On the field, Eugenio Baena, a radio reporter, rallied nearly 2,000 fans by giving a countdown to Williams's arrival. Williams felt like a fighter ambling into the ring.

The boys in enough uniform colors to fill a box of crayons were riveted. To Williams's credit, they stayed focused without ever touching a ball or a bat. After Williams stressed the importance of striding into the pitch, one boy asked precisely how far he should stride. Ten inches? Eleven? Eleven and a half?

The last leg of Williams's trip involved a 90-minute drive from Cartagena to Barranquilla along the Highway of the Sea. For every burro pulling a farmer on the narrow shoulder, there were a dozen officers with automatic weapons.

Still, Williams was so relaxed he took a nap. He also recalled how Joe DiMaggio once said to him, "Keep it up. You're doing good," and regretted that he was too fearful to ask DiMaggio for an autograph. Mickey Mantle, another legendary Yankees center fielder, signed a ball for Williams and wrote, "To Bernie. You're great." Williams laughed because Bernie Williams Jr., his 14-year-old, scribbled on the Mantle ball as an infant.

In Barranquilla, Williams was greeted in shallow right field by seven dancers and a five-piece band at Tomas Arrieta Stadium. This was not Challenger swooping in from center field at Yankee Stadium. This was the type of reception that turned a blighted stadium into a carnival, and Williams was the lead dancer, the only dancer.

The fans chanted "Williams," followed by three claps. Williams told the 90 boys and one girl in the clinic that their town reminded him of Alta Vega, P.R., where he was raised, and a chord was struck.

"I hate the Yankees, honestly, because I like the Braves," said Cristina Vargas, the only girl present. "But Bernie? He's Bernie."

Sylvio Gonzalez, a United States Embassy officer, said local baseball historians had told him Williams was the first American player to visit Colombia and conduct clinics since Al Rosen of Cleveland did so in 1947.

"I'm telling you," Gonzalez said, "he's a rock star here."

Williams really was a rock star, or at least a music star on his last night here. He had resisted invitations to play at a jazz club in Venezuela; despite his talent as a musician with a best-selling jazz album, he is self-conscious about performing. A nervous Williams said the concert would be the hardest part of the excursion.

If it was hard, Williams and the band of college students made it look as if they had been playing together for a year, not an hour. The students planned to learn songs from "The Journey Within," Williams's album, but they did not have the sheet music, so Williams crammed to learn their tunes.

He began the show with a guitar solo and band members tried, but could not suppress huge grins. Whenever Williams needed direction, he looked to 21-year-old Kabir Suescun. At one point, Williams traded guitars with Suescun, causing Sexton to say, "There's a cultural exchange." Williams then played a call and response set with Thomas Teheran, who was on the timbals. Teheran deftly banged away and stared at Williams. Williams, his shoulders hunched and a fake glare on his face, returned musical fire by picking at Suescun's guitar.

There was a blackout during the concert, but the only person who reacted was the military official guarding Williams. The band kept playing. For their encore, Williams and the students strolled out wearing Yankees caps.

After Williams barreled through days that lasted 14, 16 and 18 hours, it was not all that surprising that he got sick. A doctor said Williams had a viral infection and wanted to give him two injections, but Sexton turned into a part-time doctor and said that was unnecessary.

A pale, perspiring Williams was hurting as the trip ended. Once he passed through four security checkpoints here, Williams nestled into Seat 3K on Avianca Airlines Flight 38, covered himself in two maroon blankets, planted a pillow against the window and slept. It was time to go home.

But five intense days had changed everything. Williams made connections he said would always be with him. Because of those five days, Williams's world had changed. Because of Williams, two parts of the world had perhaps changed a little, too.