Former USC quarterback Sam Darnold threw 846 live-action passes over the last two years with the Trojans, but the most important passes thus far in his football life will be thrown on Wednesday.  

Fair or not, it’s certainly odd. Darnold will be wearing shorts and a t-shirt and won’t be dealing with a hostile defense, but because the highly-touted 20-year-old didn’t participate in passing drills at the NFL Scouting Combine, this will likely be his best chance to prove he’s worthy of being the No. 1 overall pick in the 2018 NFL draft. 

His in-game accomplishments got him here, but a strong performance at USC’s pro day might officially separate Darnold from a crowded group of potential top picks that includes fellow quarterbacks Josh Rosen (UCLA), Josh Allen (Wyoming) and Baker Mayfield (Oklahoma). 

The Browns Are Watching (like…all of them)

Cleveland holds the top pick in the draft, and Jordan Zirm of ESPN Cleveland believes that Darnold’s pro day is the only one that the Browns “are sending their full contingent to.” The team was present at Mayfield’s and Rosen’s pro days, but head coach Hue Jackson and general manager John Dorsey did not attend. Allen will participate in Wyoming’s pro day later this week. 

The difference, of course, is that Darnold was the only member of that quartet who didn’t throw at the combine. While teams have a lot of college tape to work with, this will present many evaluators with their first chance to get up close and personal to examine Darnold’s mechanics in somewhat of a vacuum. 

But Brad, football isn’t played in a vacuum! You’re right, Steve (at least a few folks reading this are named Steve and are tripping out right now), but pro days and/or combine performances carry weight because they can either serve as icing on the cake or as cautionary tales for prospects whose stocks may be inflated by offensive systems, supporting casts or quality of college opponents. 

It wouldn’t be surprising if Darnold, Rosen, Mayfield or Allen went first overall. They’ve been grouped together tightly by a lot of analysts. And when that’s the case, one’s pro day performance matters. 

About that elongated throwing motion…

That’s especially the case with Darnold, because he didn’t throw at the combine and because all eyes will be on his throwing motion. 

As NFL.com’s Chase Goodbread pointed out, there have been “scouting concerns that his delivery can be too elongated.”

But Darnold isn’t going to start poking around under the hood at this juncture. 

“I’m not trying to change my throwing motion at all,” he told Goodbread earlier this month. “I think I get the ball off pretty quick. There is kind of a wind-up, but I think I get it off quick and that’s what matters.”

He did say he can shorten his delivery if needed, but that probably means he’ll wait for the team that drafts him to advise him there. 

“The motion I have is what got me to this point, and I really haven’t gotten into trouble with it,” he said, per Goodbread. “It doesn’t change how fast I get the ball out. If I need to shorten up and get the ball in right now, I’m able to shorten my release and get it to them,” he said. “But if I need to throw it downfield, I’ve had a tendency of really cocking back and trying to let it go, where I just have to get my hip through more. That’s something I’ve been working on, but I don’t think it’s changing. My throwing motion is fine.”

Zirm posted video on Saturday that showed the same motion:

Darnold turned the ball over 22 times in 2017, and if NFL clubs believe his release played a role there, they could be looking for him to prove that he can make that mechanical adjustment successfully before spending a first-round pick on him. That could happen when Darnold has private workouts with teams in the coming weeks, but it’d help if he could at least show just how quickly he can get the ball out on Wednesday, regardless of his motion. 

Rain or Shine

While weather forecasters are wrong almost as often as mock drafters, it does appear there’s a decent chance it’ll be raining when Darnold takes the field for his workout on Wednesday. Yet ESPN’s Adam Schefter reported he’ll throw regardless of precipitation.

That being the case, Jackson, Dorsey and other executives representing teams that could draft Darnold might consider performing rain dances Wednesday morning. Because football is messy, and I think a lot of folks would be interested in seeing Darnold throw in less-than-perfect conditions. 

Obviously, Darnold is confident in his ability to deliver in the rain. And if he’s going to wind up in a market like Cleveland, New York or Buffalo, that’ll come in handy. 

If it’s raining Wednesday in Los Angeles, there’s an even higher chance Darnold’s pro day performance will make or break him as a potential top pick.  

A Case Study

A couple months prior to the 2014 NFL draft, Mike O’Hara the Detroit Lions official stie pooled the results of 13 mock drafts in order to get a feel for where most analysts had top prospects going. The consensus at the time was that Blake Bortles was the top quarterback in the draft, but that Teddy Bridgewater was 1-A. 

Bridgewater was projected to be a top-five pick in 11 of the 13 mock drafts O’Hara reviewed. 

Two weeks later, Bortles and Bridgewater participated in their respective pro days. Bortles’ performance was widely praised, which along with a strong combine showing cemented his spot atop the quarterback pecking order. 

But Bridgewater bombed at Louisville’s pro day—a performance which was probably magnified because he didn’t participate in passing drills at the combine. 

Six weeks later, Bortles was the third overall pick of the draft. Bridgewater slipped to the No. 32 spot. 

That might not necessarily be the case with Darnold, but it goes to show that pro days can make a hell of a difference. Johnny Manziel might not have been a first-round pick if not for a strong pro day, while Carson Wentz might not have been picked second overall had he not put on a show at his. 

Darnold’s pro day might not determine whether he becomes a successful NFL quarterback, but there’s a good chance it has a major impact on where he’s drafted next month. 

Brad Gagnon has covered the NFL for Bleacher Report since 2012.

Follow @Brad_Gagnon