After trading away four-fifths of their starting rotation in a matter of days back in July, the Red Sox rebuilt their rotation in a matter of days in December and now have a plethora of starting pitchers.They have a rotation that now includes Clay Buchholz, Rick Porcello, Wade Miley, Justin Masterson and Joe Kelly. Waiting in the wings are Brandon Workman, Matt Barnes, Edwin Escobar and Steven Wright. Waiting to break through from the minor leagues are Eduardo Rodriguez, Henry Owens and Brian Johnson. If it were just a matter of numbers, the Red Sox would be set. Every team needs more than five pitchers to get through a season. Last season the Sox used 11 different starting pitchers. Buchholz led the staff with 28 starts, while knuckleballer Wright made just one as the Sox stumbled to a last-place finish. But even in their World Series championship season of 2013, the Sox used 11 starters. But, that brings us to the big question: Who will be the Red Sox ace? Is he already on the roster or have the Red Sox not acquired him yet? If the latter, who is it? The Sox were $20 million and a couple of years short on their best offer to Jon Lester, a known commodity. They weren?t seriously in on the serious bidding for Max Scherzer, who went to the Nationals. What about James Shields? Will they empty the minor league of prospects for Cole Hamels? Jordan Zimmerman? Doug Fister? Stephen Strasburg? “Starting pitchers who perform at the highest level and do so consistently and are relatively young and near their prime, those guys are hard guys to get and are valuable and cost a lot, whether it?s dollars or talent,” said general manager Ben Cherington. “As far as starters, we?re really focused on the guys we have. Look, we always have to keep an open mind with opportunities, but we like the group we have.” Not everyone feels as strongly. “I give their rotation a B-/C+,” said one major league scout. “Starting pitching looks like a bunch of No. 3s and 4s. I do not see any No. 1 or 2 starting pitchers. They will surely miss (John) Lackey and Lester. I think they can compete but are going to need a serious offense to help these guys out. Miley and Buchholz probably have the best stuff and I would not go better than No. 3 on those guys. Miley brings some innings and grit, a Jake Peavy type, though he is not a hard worker. Masterson and Kelly are good No. 4 depth and hoping for upside. Porcello has wildcard upside and has improved over the last two years. I think it?s a B-/C+ starting pitching staff. Not great but solid across the board. They will need a horse at some point, by July if they?re still in it.”It?s not just the number of pitchers that gives a team its starting depth. It?s the quality of those pitchers.? Buchholz, who turned 30 in August, would be expected to be the leader on the staff. Does he have the stuff? Yes. But, entering his ninth major league season ? and despite throwing a no-hitter in his second major league start — he has yet to demonstrate he has the maturity or is ready to take on that responsibility. Last season he went 8-11 with a 5.34 ERA. He has yet to make 30 starts or throw 200 innings. According to fangraphs.com, the average velocity on his fastball and cutter last season was down compared to his career average. His fastball velocity has dropped steadily every year since 2010. His year-to-year ERA has seen wild fluctuations, including swings of 2.82 3.60 over the last three seasons. While we have seen the stuff that could make him an ace, he has yet to demonstrate any consistency.? Porcello was acquired by the Sox in a trade with the Tigers in December. A first-round (27th overall) pick by the Tigers in 2007, the right-hander turned 26 in December. He matched a career high with 32 starts, going 15-13 last season, the most wins he?s recorded in six big league seasons (also the most losses), with a career-best 3.43 ERA over a career-high 204 2/3 innings, with 129 strikeouts and 41 walks. His ERA has