Free-agent catcher Victor Martinez is bolting the Boston Red Sox to sign with the Detroit Tigers, according to multiple media reports on Tuesday.

Two weeks ago, Red Sox general manager Theo Epstein expressed his strong interest in re-signing Martinez and third baseman Adrian Beltre. But he acknowledged competition for the players.

"It always comes down to dollars and years," Epstein said.

Martinez will receive a four-year deal for $50 million, according to Venezuelan reporter Ignacio Serrano of El Nacional, who first reported the agreement. The Associated Press reported that the deal is pending the results of a physical. Martinez made $7.7 million last season.

The Red Sox offered Martinez a choice of a three-year, $36 million deal or a four-year contract for $42 million, according to a major league source. The source said the Red Sox had not been informed of Martinez's decision, but the team was not surprised to hear that he would play elsewhere.

The Orioles and White Sox were also outbid, according to the El Nacional report.

"When guys get to free agency, there are a lot of decisions that have to be made," Red Sox manager Terry Francona said on the "Dale and Holley" program on Boston sports radio station WEEI. "One is by the player, one is by the organization and one is by other teams. Sometimes it doesn't work out where a guy comes back, but that doesn't mean we're not going to be any good. I feel real confident. The winter has to play itself out, it's just beginning and it will be really interesting."

Martinez is a Type A free agent and the Red Sox offered him arbitration, meaning the team will receive compensation for his signing with the Tigers. The Red Sox will receive the Tigers' No. 1 pick (No. 19 overall) and a first-round "sandwich" pick, a selection that will come after the regular first round and before the second round. The Red Sox also offered arbitration to Beltre and Felipe Lopez, while not offering to Bill Hall and Mike Lowell.

The 2011 draft class is anticipated to be very strong, and it may be the last in which the Sox will be able to employ their very successful strategy of paying above slot in later rounds for premium talent that dropped because of contract demands. With the collective bargaining agreement due to expire next November, the draft is expected to undergo extensive revisions as part of negotiations.

The switch-hitting Martinez was extremely productive for the Red Sox since his acquisition from Cleveland at the 2009 trading deadline. Martinez, who turns 32 on Dec. 23, batted .313 in 183 games with the Red Sox, with 28 home runs and 120 RBIs.

Last season, he was the only big league catcher in the majors to hit .300 or better while hitting 20 or more home runs, despite missing 22 games with a fractured left thumb. He was dominant against left-handed pitchers, batting .400, slugging .742 and posting a 1.173 OPS

Martinez is a lifetime .300 hitter, a four-time All-Star and also plays first base.

Jarrod Saltalamacchia, who was acquired from the Rangers last season, becomes No. 1 on the depth chart at catcher for the Red Sox. The team declined to offer arbitration to longtime catcher Jason Varitek, but remains interested in bringing him back, according to club sources.

"A switch-hitter with power, I think we view him potentially as somebody that can really fit the bill as maybe an everyday catcher with us," Francona said of Saltalamacchia, while adding that the Red Sox aren't just handing him the job.

The Tigers lacked production from the catcher's spot last season. Rookie Alex Avila, 23, batted .228 in 104 games, while 30-year-old Gerald Laird hit just .207 in 89 games.

Detroit already re-signed third baseman Brandon Inge and shortstop Jhonny Peralta this offseason, and the Tigers added reliever Joaquin Benoit last week. They were looking for another big bat to go along with Miguel Cabrera, who hit .328 with 38 home runs in 2010 and finished second to Josh Hamilton in the AL MVP vote.

Despite Cabrera's efforts, the Tigers finished only eighth in the American League in runs. They were hurt by injuries to Inge, Magglio Ordonez and Carlos Guillen.

Ordonez is recovering from right ankle surgery and played only 84 games. The Tigers did not exercise his $15 million option, so he's a free agent. Detroit announced Tuesday it would not offer arbitration to Ordonez. The Tigers also declined arbitration to outfielder Johnny Damon, Laird and pitchers Jeremy Bonderman and Bobby Seay.

General manager Dave Dombrowski, who declines comment until agreements are finalized, has left open the possibility Ordonez could return to the Tigers. Now they'll receive no compensation if he signs elsewhere.

Detroit finished 81-81 in 2010, which was good for third place in the AL Central.

Information from ESPNBoston.com's Gordon Edes and The Associated Press contributed to this report. Ignacio Serrano is a regular contributor to ESPNdeportes.com.