The left guard typically blocks a 300-pound defensive tackle with a lot of strength but limited mobility. Conversely, the left tackle typically blocks the opponent's best pass rusher - usually a 260-pound end with explosive quickness and superior athleticism.
When Tennessee left tackle Dallas Thomas suffered a sprained knee midway through Game 2 with Cincinnati, sophomore left guard Alex Bullard had to slide outside and fill the void. Though thrust into the position unexpectedly, he handled the assignment remarkably well.
"I thought he did a good for just hopping out there ... 'Hey, you're playing left tackle,'" Tennessee offensive coordinator Jim Chaney said this week. "He did a good job and made a lot of nice plays for us."
Even Harry Heistand, who is not prone to hand out compliments, praised Bullard's effort.
"He did OK," the Vols' offensive line coach said. "He went out and competed. Alex is a competitor, and he's going to give us great effort wherever he plays. We're pleased with the way he competes. That's the most important thing to us."
Bullard thinks his abrupt move from left guard to left tackle went well but admits that the blocking assignments represent a stark contrast.
"It's a major adjustment in the passing game because you're blocking a faster, quicker guy," he said. "You have to be on your feet a little more at guard because the 3 techniques (defensive tackles) are right up on you. You just have to know who you're going against and how they escape blocks."
Bullard could be a key figure in Saturday's game at No. 16 Florida. Should Thomas aggravate his knee injury, Bullard again will have to fill in at left tackle. That means he'll be protecting the blind side of one of America's hottest quarterbacks. Tyler Bray is completing 78.5 percent of his throws and averaging 349 passing yards per game, with seven touchdowns and zero interceptions to date.
"We just need to continue to protect Bray and give him time," Bullard said, "because if we give him time he's going to shred anybody that we play. We're really confident in that."
This has been a year of adjustments for Bullard, a native of Franklin, Tenn. He transferred from Notre Dame to Tennessee last winter so he could be closer to his family in the wake of his father's death. He moved from tackle to guard to center during spring practice, then back to guard midway through fall camp. Now, depending on the condition of Dallas Thomas' knee, Bullard may be playing left tackle for a while.
"Obviously, going to left tackle wasn't something I expected to do but it was something I prepared my mind for," he said. "The coaching staff has made it clear that I'm going to have to play three different positions (center, left guard, left tackle) if somebody gets hurt. That (left tackle) is what I played all through high school, so it isn't that much of an adjustment for me."
Perhaps, but playing tackle against a stout Florida defensive line could be quite an adjustment. The Gators are far more formidable upfront than the Montana and Cincinnati lines Tennessee faced in Games 1 and 2.
"Obviously, it's going to be a big test for us," Bullard said. "We'll be going against a little bit different type of defense."
Although Tennessee head man Derek Dooley said this week that the Gators "probably have the most talented defensive line in the country," Bullard and his mates are not at all intimidated.
"We're extremely confident as an offensive line," he said. "We have a lot of talent and a lot of depth. It'll be a good challenge but we're excited to take it on."
When Bullard moves from left guard to left tackle, freshman Marcus Jackson moves from the bench into the left guard slot. Bullard thinks the rookie performed well while seeing extensive action in Game 2.
"When he got in we really didn't miss a beat," Bullard said. "I was in his left ear and James (center James Stone) was in his right ear. We just made sure we were all on the same page. Marcus is going to be a great player. When he goes in the right direction he can hammer some people."
In addition to starting at left guard and filling in at left tackle, the 6-2, 309-pound Bullard is the top reserve at center. That kind of versatility makes him incredibly valuable.
"You can't overlook that," Chaney said. "We have several of those kids in the front that can move around and play a bunch of different places. As experience comes their way they'll be able to do it more and better. That's tremendous."
Whatever position/positions he plays Saturday at The Swamp, Bullard hopes to help Tennessee generate some rushing yards. The Gators are sure to focus on stopping Bray from throwing the ball to his elite receivers, Justin Hunter and Da' Rick Rogers.
"They're going to know about Bray, Justin and Da'Rick, and they're going to try and shut those guys down," Bullard conceded, "so we're going to have to run the ball to have a balanced attack."
Although Tennessee produced just 126 rushing yards in Game 2 vs. Cincinnati, Bullard saw some positive signs.
"If you look at the film there's some shots of all of us getting some good licks on people, everybody running to the ball and finishing off blocks," he said. "I feel like we physically beat Cincinnati on the offensive side of the ball.
"I believe we ran the ball better but there's still room for improvement. We just need to keep working at it, and we'll eventually get there.... There were a few times Saturday when we did split 'em for big gains. There were holes there."
Offensive lineman Alex Bullard clears a hole during the Cincinnati game.