CLEMSON -- Sidelined with a sore back Saturday, Kyle Parker watched Clemson's second scrimmage wearing a long-sleeve T-shirt and baseball cap. What the starting quarterback witnessed "wasn't pretty," according to offensive coordinator Billy Napier.

Some of the offensive woes can be attributed to mixing and matching first- and second-team offensive linemen, a sort of in-game tutoring exercise.

Some of the defense's dominance can be explained by its superior depth.

But the offensive struggles at Death Valley can also be attributed to this: backup quarterback Tajh Boyd is behind where Parker was a year ago, when Parker began an arc of performance culminating with freshman All-American honors.

Clemson's first-team defense didn't allow a touchdown and rarely allowed a first down. Procedural issues often sent the offense stumbling backward, with Boyd drawing coach Dabo Swinney's wrath after a delay of game penalty in a two-minute drill situation.

Clemson quarterbacks were intercepted three times and did not connect with a wide receiver for a completion of 10 yards or more.

"He's further behind than (Parker) was," Napier said of Boyd. "K.P. had a little bit more of a foundation than Tajh did in terms of being a coach's son, being around a lot of football. His dad played professional ball. He had a little quicker transition. But it's very similar in terms or where we are starting and where we are finishing. But I think K.P. proved to process things a little faster last year.

"But we all knew that was going to be the case."

Boyd is Plan B should Parker opt to play baseball exclusively. The redshirt freshman took a step back from his debut last week.

He was intercepted on his first series, underthrowing a corner route, and completed only one of his first eight passes.

He finished 4 of 11 passing for 39 yards and a touchdown. He was intercepted twice.

In two scrimmages, Boyd has completed 11 of 25 passes for 91 yards, two touchdowns and two interceptions.

For comparison, Parker threw five touchdowns against no interceptions in his first two scrimmages last spring, completing 9 of 26 passes for 174 yards. Parker finished with a stellar spring game, completing 13 of 21 passes for 171 yards and a touchdown.

Swinney says it is unfair to expect Boyd to match Parker's spring of 2009.

"Kyle's (high school) quarterback coach for two years (Carl Smith) is now with the Cleveland Browns," Swinney said. "Kyle just has a greater foundation. Everyone is at different levels."

Swinney hopes to have Parker back next week after allowing his back a few days to rest.

"It's been kind of sore the last few days," said Swinney, who said the injury is nerve related. "We'll sit him out (Saturday) to give him day's break from football and baseball."

Boyd did connect with Andre Ellington on a wheel route for a 25-yard touchdown against the second-team defense, the only touchdown in non-goal line situations.

"Last week it was more of a one-progression thing; (Saturday) I actually went through my progressions," Boyd said. "Some things were open, some were not."

While Boyd struggled, he was facing a defense deeper and more experienced than the offense.

The second-team offensive line that has become further weakened with the loss of Wilson Norris to a torn ACL, played at times Saturday undersized sophomore guard Caleb Simmons (6-0, 255).

The defense limited the Tigers' top three running backs to 47 yards on 24 carries.

"That's the difference -- we just have a lot more depth on the defensive side of the ball," Swinney said. "Experienced depth, and that's obvious. They just roll guys. You have the twos out there and Jarvis (Jenkins) and Brandon (Thompson) in there.

"It's not a bad thing. You'll never hear me complain about having a dominant defense in spring training. … I hope they are not satisfied."

Gilchrist shines

Marcus Gilchrist is alleviating two concerns for Clemson this spring: the voids at cornerback and in the return game.

Gilchrist intercepted Boyd on the opening possession of the scrimmage, produced a sack on a corner blitz and stuffed Jamie Harper on a third-and-1 rush up the middle.

Gilchrist wasn't done there.

He capped his day by returning a punt 78 yards for a touchdown, showing good change of direction ability.

Extra points

Corico Hawkins and Jonathan Willard started as the first-team linebackers. Willard continued his impressive spring with a pair of interceptions and a pass defended … Former Berkeley High standout Ellington was the scrimmage's leading runner (nine carries for 26 yards) and receiver (four catches, 52 yards) …. Da'Quan Bowers was limited due to his knee … Parker and Swinney were each in the training room Saturday complaining of back stiffness; Swinney was to undergo an MRI Saturday.

Reach Travis Sawchik at tsawchik@postandcourier.com and check out his Clemson blog at www.postandcourier.om/blogs/tiger_tracks.