The major concern is the heel issues that David Ortiz, the centerpiece of the batting lineup, is experiencing, because he won’t be ready to start the season. A prolonged absence could impact the Sox considerably.

One of the major positives has been the performance of the five starting pitchers, two of whom – Felix Doubront and Clay Buchholz — had injury concerns at the outset. Doubront had a sore shoulder at the start of camp and gradually has gotten back in the mix, with positive results in his last two outings. Buchholz, who suffered a mild hamstring strain, has thrown well after a 10-day setback, working 8⅓ scoreless innings.

Jon Lester, 2-0 with a 1.29 ERA, was the first pitcher to go five innings in a start, and he appears to have corrected some of the mechanical issues he had a year ago. He’s set to be the Opening Day starter, though manager John Farrell has yet to make the official announcement.

Also, while the future is not completely in focus for John Lackey, he has responded well in his first camp since Tommy John surgery (despite an 8.10 ERA), his confidence and repertoire improving with each outing.

Veteran Ryan Dempster seems to be refining all of his pitches and shouldn’t be a concern.

Other positives include the play of prospects Jackie Bradley Jr. and righthander Allen Webster; the offensive development of defensive whiz Jose Iglesias, even though the shortstop’s average has started to dip again recently; the overall play of free agent first baseman Mike Napoli; and the defense of catcher David Ross and his potential impact on the staff.

Bradley Jr. (15 for 28 with a 1.343 OPS) has been the star of camp. The outfielder has done everything asked of him, showing great poise, speed, defensive prowess, and the ability to hit all types of pitching. The Sox may prefer he stay in the minors to develop, but there may be an outside shot he could stick if Ortiz’s injury is expected to take a while.

Iglesias, hitting .214, is showing a better approach at the plate, and it appears he would get the call if starter Stephen Drew continues to have concussion-related symptoms.

The Sox feel strongly that a starting shortstop in the American League has to be able to hit reasonably well to stick with the team. Whether that time has arrived for Iglesias remains to be seen. But opposing scouts believe he’s taking much better batting practice and being far more aggressive at the plate and believe he may be turning the corner in becoming a more all-around player. Drew was hitting .188 before suffering a concussion.

The last couple of games it appears third baseman Will Middlebrooks has begun to hit with authority again.

Ross, batting just .083, has impressed everyone with his professionalism. “He’s really going to help us,” said bullpen coach Dana Levangie.

Napoli, hitting .429 in his first 14 at-bats with two homers and a 1.429 OPS, has looked adept at first base after spending most of his career as a catcher. He doesn’t have a lot of range, but he’s more than adequate. The issue of the degeneration of his hips has not been a factor so far.

Webster, one of the two pitchers acquired by the Sox in their house-cleaning deal with the Dodgers last season, has been impressive and doesn’t appear to be far from the majors. He has 14 strikeouts in 11 innings, showing overpowering stuff at times.

Others are doing well, too. Pedro Ciriaco is hitting .321 and wearing many hats defensively; Jarrod Saltalamacchia is hitting a robust .381 with five doubles; outfielder Juan Carlos Linares is hitting .364 in 22 at-bats (although they have been mostly late-game hits, which means he hasn’t faced the best pitching); Dustin Pedroia is hitting .320 and shows every sign that his thumb is fully healed; and Ryan Sweeney is hitting .321, although he continues to show little power.

Koji Uehara has pitched five scoreless innings with five strikeouts, and Anthony Carter has not allowed an earned run in 6⅓ innings. Farrell really likes him.