NEW YORK (AP) – The New York Yankees didn’t take long to respond to Boston’s latest challenge.

Less than a week after the Red Sox upgraded their pitching staff, the Yankees added another ace to their collection, acquiring hard-throwing Javier Vazquez from the Montreal Expos on Thursday for first baseman Nick Johnson, outfielder Juan Rivera and left-hander Randy Choate.

Vazquez joins a starting rotation that already includes Mike Mussina, Jose Contreras, Jeff Weaver and possibly Andy Pettitte, a free agent negotiating with the Yankees and Houston.

Jon Lieber, coming off an elbow operation in August 2002, and David Wells, a free agent who had back surgery Tuesday, also are possibilities.

The deal is contingent on all the players passing physicals – Vazquez will return from vacation in the U.S. Virgin Islands for his exam.

Vazquez said he is excited about becoming a part of the Yankees-Red Sox rivalry.

“The Yankees are a winning team, and now I will see myself getting involved in the rivalry of that team with Boston,” Vazquez told the radio station WPAB in his hometown of Ponce in Puerto Rico. “The Yankees are a team that always wants to win, and what every ballplayer wants is to win.”

New York said it wouldn’t comment on the deal until after the physicals, citing major league rules.

Just last Friday, the Red Sox completed a deal for Curt Schilling, who joins Pedro Martinez and Derek Lowe in Boston’s rotation. Last season, the Red Sox battled the Yankees until the 11th inning of Game 7 of the AL championship series.

“I didn’t think they were just going to sit there and stand pat,” Red Sox general manager Theo Epstein said. “With their resources and their ability to attract top talent, I knew they were going to spend it, and they’re bringing in some

good players. We knew they were going to get someone. That’s one of the reasons why it was important for us to kind of go out there first and try to build our club they way we want to”

Vazquez fills one of the rotation slots that became uncertain with the retirement of Roger Clemens and the free-agent status of Pettitte and Wells. Vazquez went 13-12 with a 3.24 ERA for the Expos last season, ranking third in the NL in strikeouts with 241 in 230 2-3 innings.

“I think Vazquez is one of the better young pitchers in the game,” Expos general manager Omar Minaya said. “When he goes out there, he gives you everything.”

Vazquez threw 3,741 pitches, second in the majors behind Oakland’s Barry Zito, who had 3,747.

Johnson, 25, has been a solid hitter with a keen eye for the strike zone, but he’s been unusually brittle and could have difficulty staying healthy on the artificial turf in Montreal and San Juan – where the Expos likely will again play 22 games.

He has been on the disabled list in four straight seasons – he missed 61 games after breaking a hand while swinging a bat last season, strained his left wrist in 2002 and strained his left thumb in 2001. The year before that, he was out the entire season with a strained muscle in his right hand.

When healthy, he’s been productive – he hit .284 with 14 homers, 47 RBIs and a .422 on-base percentage.

Rivera, 25, hit .266 with seven homers and 26 RBIs in 173 at-bats and has a strong throwing arm, but was viewed as backup material by the Yankees.

Choate, 28, pitched only 3 2-3 innings over five relief appearances for the Yankees last season, compiling a 7.36 ERA. He went 3-5 with one save and a 3.91 ERA in 54 games at Triple-A Columbus.

Montreal, which is owned by the other 29 teams, is faced with payroll limits.

Vazquez, eligible for salary arbitration, probably will get a raise to between $8 million and $9 million. He is eligible for free agency after next season, and the Yankees initially insisted they be given a 72-hour window to work out a longterm contract.

But the Expos didn’t want to grant it and, ultimately, the Yankees felt comfortable they could work out a deal with Vazquez’s agents, Sam and Levinson.

Johnson is eligible for salary arbitration for the first time this winter and is likely to have a salary between $1 million and $1.5 million; Rivera isn’t yet eligible.

Montreal also faces on a decision by Sunday whether to offer salary arbitration to star outfielder, Vladimir Guerrero, who became a free agent.

“This gives us flexibility in putting our team together for next year,” Minaya said. “It allows us the possibility of using some of the savings from Vazquez on some free agent players.”

Without Vazquez, Montreal’s available starters include Tomo Ohka, Zach Day, Claudio Vargas and Livan Hernandez – plus Orlando Hernandez and Tony Armas Jr., both coming off injuries.

In other Yankees news, Gary Sheffield took a physical Thursday, a step toward completing a $39 million, three-year deal, which will include about $15 million of deferred money.

Also, the Yankees have begun discussions that likely will lead to the departure of Gordon Blakeley, their senior vice president of baseball operations, who is based in Tampa, Fla. Mark Newman, Blakeley’s predecessor, probably will reclaim his old job.