Red Sox pitcher Josh Beckett was sterling in his last game, shutting down the Angels in the division series. In seven career playoff games, Beckett is 3-2 with a 1.74 ERA.

The Providence Journal / Bob Breidenbach

BOSTON — So, who is the best pitcher in the American League? What happens tonight at Fenway Park will go a long way toward settling that issue.

Most Red Sox fans are assuming that Josh Beckett sewed up this year’s Cy Young Award a few weeks ago when he won his 20th game. Not so fast. You can’t rule out Cleveland’s C.C. Sabathia, the 6-foot-7 lefty with a sizzling fastball and oodles of confidence. Tonight’s Beckett-Sabathia matchup in Game One of the American League Championship Series gives baseball fans an inside look at not only the two top contenders for the Cy Young but also a peek at two of the premier pitchers in the game.

“It’s going to be a great match-up,” said Boston manager Terry Francona. “Their guy is one of the best in the game, we feel like our guy is one of the best in the game. I think when you get to this time of the season, it’s pretty awesome, and that’s why we’re playing this game. Anything less would be a little disappointing.”

The numbers were very close between the A.L.’s top righty (Beckett) and lefty (Sabathia). Beckett’s 20 wins led all of baseball but Sabathia was right behind with a 19-7 mark and he had a better ERA (3.21 to 3.27) in nearly 40 more innings. Sabathia struck out 209 batters, Beckett 194. Opponents hit .245 against Beckett and .259 against Sabathia. Beckett walks more hitters and is more prone to surrender home runs. Sabathia tends to overthrow at times, all but willing his fastball into the upper-90’s and losing some control.

The pitchers weren’t playing up their duel yesterday. Sabathia is only hoping to bounce back from a rocky first playoff start last week against the Yankees when he gave up two home runs, walked six and left the game after five innings and 114 pitches. Beckett is coming off a masterful, complete game four-hit shutout of the Angels last week at Fenway.

“I go out and do what I’ve been doing,” he said when asked about facing one of Cleveland’s two aces. “Our hitters have to worry about C.C. Sabathia, not me. I’ve just got to get their guys out.”

Beckett is clearly hoping his post-season roll continues. His last two starts have both been gems. Before his shutout of the Angels, Beckett’s previous playoff start came when he shut the Yankees out in Game 6 of the 2003 World Series, nailing down the world championship in the process. In seven career playoff games, Beckett is 3-2 with a 1.74 ERA and three complete games.

Asked what he likes so much about this time of year, Beckett shrugged his shoulders and said, “You know it’s easy on days when you’ve got everything working for you. It’s those days that you don’t have everything going that are the days you’ve got to grind it out and hope you score a couple more runs than they do. The other day [vs. the Angels] was just one of those starts that I had everything going and everything worked in my favor.”

Much has been written this year about Beckett’s maturation from a thick-headed, hard-thrower who insisted on firing fastballs in tight spots last year to a more mature, true pitcher this year. No one ever questioned Beckett’s skills, least of all Francona. That’s something the ace pitcher certainly appreciates.

“He has a lot of strengths. You know, he manages when he needs to manage, but when he doesn’t need to manage, he doesn’t try to over-think things,” said Beckett. “He just lets us go out there and lets our abilities take over and lets us play. For me, this year has kind of been about gaining his trust and in those situations where sometimes maybe he would take some guys out, he’s left me in there. That’s a big thing to have from a manager.”

At times last year, Beckett’s hot demeanor would get the best of him. While his Texas fire still shows through, Beckett says he’s grown mentally as his performance has soared.

“Have I had to channel it? Yeah, I definitely think that you learn how to deal with certain parts of your personality over time,” he said. “Your whole life you’re kind of learning who you’re going to be and what’s going to drive you, and that’s kind of where I’m getting to.”

kmcnamar@projo.com