PORT ST. LUCIE, Fla. – At the crack of the bat, Carlos Beltran put his head down and took off running from second base. To him it was the natural thing to do. To the New York Mets, boy, was it a tense 180 feet.

Testing his right knee for the first time this spring, Beltran scored from second base with a slide into home plate. More important, he bounced right up.

“Once I’m playing games I’m not thinking about being cautious,” Beltran said after getting a hit in a 6-5 win over the Boston Red Sox on Sunday.

The five-time All-Star outfielder was the Mets’ designated hitter. A switch-hitter, he batted left-handed in the second inning and lined a single to right field off Michael Bowden. On Daniel Murphy’s two-out hit, he ran for home.

Boston had plenty of reason for its own concerns. Red Sox designated hitter Daniel Nava played catch up all day. He arrived at Boston’s spring training facility at 8 a.m. Too bad, the bus left at 7 for the trip. Thinking he was staying back for a workout because of a travel-roster mix up, Nava had to make the long drive alone. He struck out in his first at-bat.

Settled in for his second turn, he hit a ground-rule double off Mets starter Jonathan Niese. Nava finished with two hits.

Bowden started in place of Jon Lester, who was scratched because of the flu and did not make the 2-hour, 20-minute trek from Fort Myers.

“I know some of the fans grumble, but it’s really fun for our staff to spend the whole day with these (young) guys and get to know them,” Manager Terry Francona said about the lack of Red Sox stars at the game.

WHITE SOX: All-Star reliever Matt Thornton agreed to a $15 million, three-year contract that adds two years and $12 million to his previous deal.

The 34-year-old Thornton went 5-4 with a 2.67 ERA and a career-high eight saves last season.

He fanned 81 in 602/3 innings to become the first White Sox reliever to lead the AL in strikeouts since Keith Foulke in 1999.

MEETING: The unions for major league baseball players and umpires have held a rare joint meeting with management.

Sunday’s 2½-hour session originally was set at the request of the players’ association after a series of missed calls in the playoffs.

Several former players attended the session.

YANKEES: Alex Rodriguez hit his first home run of the exhibition season and the Yankees outslugged the Astros 10-8 in Kissimmee, Fla.

BLUE JAYS: Jose Bautista had a productive, 3 for 3 day at the plate in Toronto’s 5-0 win over the Pirates in Bradenton, Fla.

PHILLIES: Cliff Lee threw four shutout innings and the Phillies beat the Rays, 5-4.