BOSTON – As Justin Masterson emerged from the Red Sox clubhouse after yesterday’s game against the Angels, the dozen or so family and friends waiting for him greeted him with a robust cheer.Well deserved, too, considering the outing the young right-hander had just presented for the Sox in his first big-league appearance. Despite the 7-5 loss to the Angels, Masterson provided a bright spot yesterday and a glimpse into the near future.With the sickness that has hit the Sox clubhouse, especially among the pitching corps, Masterson, 23, who had never pitched above Double A until yesterday, was pressed into service.Although he was not involved in the decision, Masterson, the Sox’s fifth pick in the 2006 draft out of San Diego State, threw six near-flawless innings, allowing a run on two hits and four walks, and striking out four. The lone run was a home run by Mike Napoli in the fifth inning.”Impressed (and) proud,” Sox manager Terry Francona said. “He handled himself just like you would hope. That’s a lot to ask a kid coming out of Double A. He competed. He had composure. He knew what he wanted to do and he did it. He did a great job. As an organization I don’t think we could be prouder.”Masterson is the first Sox starter to allow two or fewer hits while going at least six innings in his big-league debut since Billy Rohr’s complete-game one-hitter at Yankee Stadium April 14, 1967. The two hits allowed tie him with Daisuke Matsuzaka for the fewest by a Sox starter this season.Masterson induced 11 of 18 outs on groundballs, compared to 3 fly-ball outs, a testament to his sinker. He mixed the sinker in with a developing changeup and slider to keep the Angels off-balance.”When he left spring training, when we talked to him in spring training, he said that he wanted to work on his changeup and that’s exactly what it looks like he did,” Francona said. “(He’s) got great, tremendous late movement on the two-seamer (fastball). And, as those secondary pitches come, which they are, he’s going to be a complete pitcher. His poise, knowing what he wants to do, knowing his strengths, he’s a very solid young man.”Masterson found out about the emergency duty Wednesday night while he was at home with his wife.”(The Portland pitching coach) called, Mike Cather, and said, ‘Are you ready for your start?'” said Masterson, who was scheduled to start for the Sea Dogs yesterday and answered in the affirmative. “He said, ‘Well, good, it’s going to be at Fenway.’ Then I scrambled to get everything together and drive down here.”Honestly, I didn’t think he was serious, even though I didn’t think he was joking. I thought maybe he misspoke and meant (Triple A) Pawtucket. I got to the field in about 10 minutes and everyone was saying, ‘Congratulations.’ And I thought, ‘I really am going?’ It was pretty awesome.”Masterson, who pitched at Fenway last year during the Futures at Fenway minor-league doubleheader, was undaunted by the prospect of pitching in front of 37,848. Of his 95 pitches, 58 were strikes. He handed the bullpen a 3-1 lead when he left the game.”Really just putting the team in an opportunity to win,” he said, of what most pleased him about his outing. “I think that’s what the starting pitcher’s role is to do. Coming up, I was hoping to help out. There are some unfortunate things that happened and we didn’t get the victory (yesterday), but I just wanted to go in, throw a lot of strikes. I did walk four people, but other than those four walks, I pounded the zone pretty good and was happy with that.”I think I threw more changeups this outing than I have the whole season so far. But it’s really nice. (Catcher) Kevin Cash back there, mixing up the pitches? I was real happy with how the changeup looked. Mixed in some sliders and used what got me here: the sinker. I was actually real happy with the mix that took place.”As was Cash, who was starting his fourth consecutive game in place of the ailing Jason Varitek. Cash had caught Masterson several times du