SEATTLE -- If the Red Sox are going to be competitive in the American League East, they are going to need competition among their starting pitchers.
If the past two games are any indication, they are getting just that.
Just 24 hours after lefty Franklin Morales threw seven shutout innings in what turned out to be a bottom-of-the-ninth 1-0 loss to Seattle, Aaron Cook came back and did him one better with a two-hitter in a 5-0 victory over the Mariners.
Cook's gem Friday night, combined with four homers in the toughest home run park in the AL, kept the Red Sox rolling with their 10th win in their past 13 games.
"That's a huge boost those two guys have given us," rookie third baseman Will Middlebrooks said. "Morales came out last night and pitched great, and then Cookie comes out here and starts throwing that sinker.
"That's just what we need."
Cook, an All-Star with the Colorado Rockies back in 2008, has been battling injuries the past few seasons. He signed a minor league contract with the Sox just after the first of the year, then began the season in the minors.
But on a team with three starters -- John Lackey, Josh Beckett and Clay Buchholz -- currently on the disabled list (Beckett gets activated Saturday), being able to reach into the bullpen for Morales and into the minor leagues for Cook is huge.
"You can never have enough good pitching," manager Bobby Valentine said. "We're building competition here. We're building a good staff.
"We'd like to think we can give the ball to one of many guys and think we have the chance to win. Our pitchers have really gained a lot of confidence in our catching staff, especially with Jarrod [Saltalamacchia] and Kelly [Shoppach]."
While there is no guarantee that Cook will be a long-term member of the Boston rotation, the fact that he needed just 81 pitches to record his first shutout since 2009 suggests he will get multiple chances from Valentine to show it's not a fluke.
Injured much of the previous two seasons, Cook is healthy again and just salivating to get the chance to be the pitcher he believes he can be. His sinker was simply wicked, one reason Saltalamacchia kept calling it pitch after pitch.
The results were grounder after grounder. Only six of the 27 outs recorded by the Boston defense were hauled in by outfielders.
"You know [the Mariners] are going to be aggressive, but I got into a really good rhythm early," Cook said. "I depend a lot on my defense, and they played great tonight.
"It's good to be feeling healthy and making my pitches again."
Asked about the fact that he needed just 81 pitches to get 27 outs, Cook laughed and blamed it on a "short attention span."
Saltalamacchia had trouble believing the game he was catching.
"I felt like I'd caught five innings," he said, "and I looked up at the board and it was the seventh inning. Cookie was going right after them.
"When you look at what Morales and Cookie have done the last two nights, that's a big bonus for us. There aren't too many teams that go through the season using just five [starting] pitchers. We're going to need these guys, and they're stepping up."
For the first 13 innings of this series, the Mariners' pitchers were stepping up, too. No Boston baserunner had crossed the plate Thursday against Felix Hernandez or in the first four innings Friday against Hector Noesi.
Middlebrooks changed that with one swing, launching his 10th homer to lead off the fifth. In the space of eight batters, Boston would hit four homers and a double, good for all five Red Sox runs.
"He hung a slider," Middlebrooks said. "It's as simple as that."