by Clark Judge, FOXSports.com

Essentially, scouts want to check out an injured left leg on which Leftwich played the latter half of last season. A broken tibia suffered on Nov. 2 prevented Leftwich from appearing in any postseason games or workouts.

Until now.

Which makes Monday's session at Sarasota, Fla., critical for a quarterback once viewed as the best of this year's class. Remember, Leftwich is considered a top-10 possibility, which means he stands to earn millions from this month's draft — provided, of course, buyers are satisfied he's not a risk.

"He's got to prove he's healthy enough to do this for a living," said an NFC general manager. "The key things here are: 1) To show he's healthy and 2) to show he can be mobile."

No one questions Leftwich's arm. Not only is it strong, it's accurate. Though he missed a game with the injury last season, he wound up leading the country in total offense at nearly 366 yards a start. He also threw for more than 4,000 yards, completed 69 percent of his passes, had five 400-yard performances and finished sixth in the Heisman Trophy balloting.

But forget about the passing; it's Leftwich's mobility that has an army of scouts waiting to see him next week. Clubs looking for a franchise quarterback are interested if there are any lingering effects from the hairline fracture — particularly because Leftwich played on the gimpy leg for four games and because it's the same shin on which he had a previous surgery.

"I don't know that he can hurt himself with this workout," said one AFC assistant who will attend. "But he could help himself. This guy is like the Magic Johnson of football. He's so charismatic guys will follow him anywhere, and they won't blink an eye. Plus, he's smart. Real smart. He can change plays, change protections and tell runners what holes to hit. No quarterback in this draft is as smart as Leftwich.

"But it's his leg I want to see. I want to see how he sets up. How he runs. He moves around in the pocket. I just want to see him do the things I've seen of him on film the last two years."

He has company. With the first pick of the draft, the are supposed to be in the market for USC quarterback . Yet the plan to attend Leftwich's workout and, according to one source close to the organization, receivers and will be there to catch his passes. The also plan to take Leftwich back with them for a meeting in on Tuesday, while Baltimore is scheduled to sit down with him April 16.

The ' , who is represented by the same agent as Leftwich, also is expected to participate in Monday's workout.

"The key question is: Is Leftwich healthy?" said an AFC general manager whose team drafts in the top 15. "The last time we saw him he wasn't. He was playing on one leg. If he demonstrates he's healthy, and the leg isn't a problem, he solidifies his position in the top 10. But if he's gimping around or the leg hurts days after this workout that's an indication there's something wrong. How significant is the workout? Well, I'd ask: What are you looking for? Anytime there's doubt, what do we always say? Go back to the tape."

The early signals are encouraging for Leftwich. One scout who met with him recently said he was down to 236 pounds from a weight of 249 at February's NFL scouting combine. If Leftwich can run, say, a sub-5-second 40 he solidifies his status as a premier draft pick. If he doesn't, well, there still will be someone ready to invest a first-round draft choice — and probably a top-15 pick — on the guy because he's a superb pocket passer.

Besides, clubs will have an early indication what's going on when Leftwich and 40 other draft prospects recovering from injuries travel this weekend to Indianapolis for medical testing. All are expected to meet Saturday with medical staffs of individual teams.

"I love Leftwich," said one coach who drafts in the top 10, "but you've got to look down the road. You've got to wonder what happens if he's tackled and falls on his leg. All I know is that Palmer and (Cal quarterback) avoid the tackles that Leftwich may not."

Unlike Palmer, Leftwich didn't have one season of extraordinary success; he had three, including one where he threw 41 touchdown passes. But his competition didn't include opponents like Iowa, , and , either, so Leftwich has something to prove.

But let's not get carried away here: The level of competition didn't stop the New York from making Marshall quarterback a first-round draft pick three years ago, and all Pennington did was lead the NFL in passing last season.

"It's too bad," said an NFC scout. "Leftwich has put all his eggs in one basket. It all comes down to this workout. But if you look at him on film the guy is everything you want. I don't think he's going to change anyone's mind with one workout. He is what he is on tape, and that counts for just about everything."

Senior writer covers the NFL for FOXSports.com and can be reached at his e-mail address: cjudge@foxsports.com.