BOSTON –– To understand what Victor Martinez now means to the Red Sox, one need only look at what his departure meant to the team he left behind.

With hours to go before the trade deadline, the Indians clubhouse was rocked by the revelation that their leader, their rock, their heart, was leaving for Boston. For a time, they felt lost, rudderless, said catcher Kelly Shoppach.

“He was our heart and soul. He was our heartbeat and him getting traded was one of those things where –– who do we turn to? We spent a month trying to figure out, basically, what we were doing, because he was always leading us in the right direction,” Shoppach said.

Martinez arrived in Boston on Aug. 1 in a trade for reliever Justin Masterson and two minor leaguers, and immediately won fans’ hearts by delivering clutch hits. He impressed the pitching staff with grit and intelligent game-calling, and even took over a leadership role in the clubhouse despite being new in Boston.

Meanwhile, back in Cleveland, the struggling Indians felt his absence every day. Already weak, they fell further without their leader.

“There was no question, you lose a guy like Victor Martinez, that’s more than a punch in the gut: That’s almost a knockout,” said Indians reliever Jensen Lewis.

“He was the heart and soul,” Lewis said, echoing Shoppach. “He was the heart and soul here. He was our sparkplug, he was our guy that when we needed a big hit, Victor would get it. It didn’t matter who it was against. We just knew that if we had guys on, and it was a big situation, you knew who you wanted up there.”

Boston fans have learned that quickly. The Boston front office gambled by bringing in Martinez, who was an obvious talent, but as with all trades, an uncertain fit. How would Martinez fit with catcher Jason Varitek? How would the team handle the logjam at the corner infield spots? How would Martinez adapt to the media spotlight in Boston? One by one, Martinez has answered every question, and risen to the challenge despite the new environment, said general manager Theo Epstein.

“He deserves a ton of credit. I mean, he couldn’t have handled himself better than he has, on and off the field, since coming here,” Epstein said.

Martinez excelled for his new team right away. He drove in a run in his first game, and went 5 for 6 in his second. He has hit .335 with seven home runs and 36 RBI through 54 games in Boston. He ran a hitting streak to 25 games before reaching on an error in his single pinch-hit at-bat one game last week. He has looked like he played in the Boston fishbowl his whole career.

“He was the right fit at the right time for this club in that respect. And his leadership as well. I mean, obviously an off-the-charts human being, and (he) accomplished something which is hard to accomplish, which is he came seamlessly into a pennant race and provided legitimate leadership at the same time,” Epstein said.

The Indians dealt away Martinez and ace pitcher Cliff Lee in the final weeks of July. For a time, they muddled through, actually posting a winning record in August. But then things started to go wrong: star outfielder Grady Sizemore went on the disabled list Sept. 4, and the team went into a tailspin. Normally, this would be the point when Martinez would rally his team, buoying spirits in the clubhouse and delivering big hits on the field. But as Cleveland lost 11 straight through September, Martinez was in Boston, providing his clutch hitting for somebody else.

“He always had that knack to come through. When times were tough, he’d always be that guy to keep our spirits high, and provide that energy every day. That’s going to be a huge thing for the Red Sox going forward,” Lewis said.

Shoppach agreed. Martinez’s love of the game is obvious, and infectious.

“First and foremost, he’s like a little kid. He’s so excited to play every day. I don’t know how he does it. He wants to catch every night. He’s a competitor and we missed that spirit probably the most when he wasn’t around. Even last year when he was hurt, it was evident he’s an important part of what we did here. He gets traded and we all kind of took a big hit with that one,” Shoppach said.

“It was very hard to see Victor go from a leadership standpoint. I thought I loved to play the game, but he takes it to a whole new level.”

Martinez, 30, came up through the Cleveland system, and he thought he was going to stay there for some time. Even though this was an obvious rebuilding year, Martinez was committed to staying through the process and leading the Indians back to the playoffs. Things didn’t turn out that way.

“At some point I thought I was going to stay in Cleveland, and I make it clear –– I really wanted to stay, but the owners were thinking different, and it’s not my fault, it’s not [general manager] Mark Shapiro’s fault, it’s not [manager] Eric Wedge’s fault. They wanted to take a different route, a different way. It’s their team, they can do whatever they want,” Martinez said.

Martinez is in the final year of his old Cleveland contract, which pays him $6.2 million this year. He has a $7.5 million option for 2010. With overall numbers of .302-22-104, it’s a foregone conclusion that Boston will want him back, and the only question is when they will talk about locking him up long term. There’s been no talk about the next step beyond the option at this point.

“Not yet. The only thing I can manage is to go out there and play hard, like I’ve always played. So we’ll see what happens. They’ve got the option on me now, so this is the last year of my contract, and then there is the option,” Martinez said.

Without discussing his feelings on signing long-term, Martinez said he’s thrilled to be in Boston, where he was welcomed with open arms by his new teammates.

“Now I’m here, I’m really happy. There’s no place better than coming to Boston if I was going to be out of Cleveland. Now I’m going to be part of this, and it’s pretty exciting. It’s pretty exciting, and it’s an honor to wear this uniform. A lot of baseball players, it’s a dream to come to Boston,” he said.

Varitek, in particular, shocked Martinez with his openness –– considering the ferocity with which he plays.

“You play against him, and he looks kind of mean. That’s the way he plays. He’s one of the guys I always looked up to. He’s pretty smart, he knows what he’s doing, and all the things he’s done for this organization, no one’s going to take that away from him,” Martinez said.

“When I got here, it kind of surprised me, because I never knew that was the kind of person that he is. He’s great, great. He’s been there for me the whole time.”

Still, he can’t help feeling a certain tug on his emotions, seeing his longtime friends and teammates across the field –– and on the mound opposing him.

“It’s really weird when I get to face the guys I used to catch for for a long time. I had to face [Rafael] Perez yesterday. Now I have to face Jeremy Sowers. That’s weird, I know them, they know me. That’s the toughest part,” Martinez said.

They know him, and they miss him. The Red Sox are beginning to understand why.

-With reports from Sports Writer Joe McDonald

dbarbari@projo.com