LOS ANGELES -- Matt Barkley was a potential top-five pick in this year's NFL draft.
Then, once he announced he was staying for his senior season, he was the consensus No. 1 overall pick for the 2013 draft.
Now, according to ESPN NFL draft expert Mel Kiper Jr., Barkley would be lucky to go in the top 20 come April. The USC Trojans senior's stock has dropped dramatically this season, with his 15 interceptions and the Trojans' four losses playing a big role in it.
And Barkley suffered a shoulder sprain in his throwing shoulder in USC's last game, a loss to UCLA, so his college career may well be over.
"He's hurt right now, so he's not doing anything to improve his stock," Kiper said Tuesday, in a phone interview. "But I think in terms of the season, it obviously didn't go as well as he would've hoped. He wasn't as good this year as he was last year."
Several things outside of Barkley's control contributed to that, according to Kiper, including the loss of left tackle Matt Kalil and dropped passes by his star receivers. But Barkley didn't have a single signature win this season, and that hurt him.
Even more, his physical limitations came to light. Barkley is listed at 6-foot-2 and 230 pounds and may measure in smaller on both counts at the NFL scouting combine in February.
"It's not about what Barkley did or didn't do, it's about what he is physically," Kiper said. "If you're gonna overcome a mediocre year, you've gotta be great physically. You've gotta have size, you've gotta have a rocket arm, you've gotta have mobility.
"Barkley doesn't have that. He's not a guy who's gonna wow you over from that standpoint. Matt's a pocket guy who's 6-2 and doesn't have a great arm, so he's gotta be a great decision-maker, tremendously accurate and a great leader. He's gotta have all those things going for him in the NFL to overcome the lack of great physical qualifications."
Kiper pointed to former Washington quarterback Jake Locker as an example of what Barkley is not -- an elite athlete who overcame his statistical shortcomings to still go in the top 10. Locker went eighth to the Tennessee Titans in 2011.
Had Barkley come out last season, Kiper projected him as a possible top-five selection, a good bet to go to the Cleveland Browns and ahead of Ryan Tannehill.
"History, from an NFL perspective, would have been rewritten," Kiper said.
Now, Kiper projects him to go somewhere between the 20th and 40th picks, with a chance to go as high as 15th in a best-case scenario and as low as the middle of the second round in a worst-case situation.
The Senior Bowl, on Jan. 26, will help narrow that range down, Kiper said. But the longtime draft analyst also noted that Barkley's senior season won't have any impact on his NFL future -- only how it starts.
"Whatever he's gonna be, he's gonna be," Kiper said. "The year didn't have any impact on what type of NFL quarterback he's gonna be."
And Kiper left the door open for a sudden, unexpected change in Barkley's stock, pointing to all the pre-draft movement for quarterbacks in recent seasons, especially in 2005.
"Two weeks before that draft, people thought Aaron Rodgers was gonna be the No. 1 overall pick," Kiper said. "He went 24th, Alex Smith went No. 1. Now he's a great quarterback and Smith is an average one."