Winston, Mariota potential No. 1s

— -- The top two quarterback prospects in the 2015 draft class, Oregon's Marcus Mariota and Florida State's Jameis Winston, each put on a show at the NFL scouting combine on Saturday. It's rare to see the top two guys work out together at the combine like this, and the vast majority of their performances were extremely positive.

Let's get into how each did, how I have them ranked coming out of Saturday's workouts, and also take a look at how the top receivers performed.

Mariota was really, really good. But Winston was exceptional.

Some are going to focus on the measurables, with Mariota putting up fast times and good scores in the jumps and Winston being below average in most areas of his athletic testing. But I just don't think those things are going to matter with regard to Winston's chances of becoming a successful NFL quarterback.

Winston may not run fast times, but he can extend plays with his strength and instincts, and that's enough in the NFL -- especially when you factor in his ability as a passer. He is just a natural thrower of the football. His delivery was a minor area of concern, but for the most part he showcased an efficient delivery in passing drills on Saturday. He is almost always on balance, and even when he isn't, the ball is still delivered on point. He showed excellent touch on deep balls and over-the-shoulder throws.

Mariota isn't the natural passer that Winston is, and he doesn't have the same experience in a pro-style system that Winston does. That showed up Saturday, as the biggest difference between the two was in anticipation throws. Mariota was a little late on some of those, but he showed improvement during the drills. I feel as though his footwork in working from under center is better than expected given how little time he's had to work on it.

The other thing I heard from multiple people is that teams are really impressed with how good a young man Mariota is. But Winston also impressed teams in his interview sessions. I heard from several people that he has handled himself well, coming across as both sincere and confident, and that his football IQ was off the charts. It also became clear that other players, especially wide receivers, gravitate toward Winston. It's not a knock on Mariota, but it's clear he's not viewed as the same kind of vocal leader that Winston is.

These guys, to me, are both still in the mix to be the No. 1 overall pick. They have very different styles in a few different ways, so it'll come down to the preference of the Tampa Bay Buccaneers or whichever team ultimately ends up picking first overall. Personally, I give the edge to Winston as the better prospect. Mariota was really good Saturday and it's clear that some improvement is already there. But Winston confirmed what I've seen of him on tape: He is just a natural in terms of his ability to anticipate throws and put the ball on spots. There just aren't many guys out there who can throw the football like him.

Hundley was good, but it might not matter on draft day

At 6-foot-3 and 226 pounds with 10½-inch hands, UCLA QB  Brett Hundley tested well across the board and threw the ball well during drills. But that comes as no surprise to those who have studied him. The biggest concerns with Hundley are his lack of pocket presence and erratic accuracy when under pressure. So while his performances today -- and by several accounts during interviews -- have been all positive, it will be difficult to ease the aforementioned concerns during the pre-draft process.

Notes on WRs

We'll get into this year's running back class at a later time, but here are some thoughts on how the receivers did Saturday:

Cooper and White are both in the top-five mix -- and Parker isn't far behind

Alabama's Amari Cooper and West Virginia's Kevin White are our top two receivers, and both performed well Saturday. Cooper ran a really good 40-yard dash time at 4.42 seconds, and when you factor in his savvy as a route runner, his big-play ability and just his overall game, he's about as complete a receiver as you're going to see coming out of college. White, on the other hand, probably has the lower floor but higher ceiling. He had one great year of college production, but based only on that one year he showed better ball skills (Cooper's are still really good), he's bigger at 6-3, 215 pounds (Cooper is 6-1, 211), and he put up a wow time in the 40 at 4.35 seconds.

Both had surprisingly low numbers in the vertical and broad jumps, considering what good athletes they are, but both looked good in the pass-catching drills. I think both are in the mix to go as high as No. 4 overall to the Raiders, and while Cooper might have had a clearer edge coming into Saturday, White's speed at his size makes it an even more intriguing debate.

Our No. 3 WR, Devante Parker, got kind of overlooked Saturday, but he had a really good workout. He's close to White's size and ran an impressive 4.45 40 and did significantly better in the vertical and broad jumps (both of which have a correlation with pro success for WRs) than Cooper and White. When you factor all of that in, I don't think there's much of a difference between the workouts of all three. Parker also belongs in the top 20 prospects, and solidified that status with his performance Saturday.

Big WR prospects could be in high demand

Beyond the aforementioned WR trio, Arizona State's  Jaelen Strong (6-2, 217 pounds) and Oklahoma's Dorial Green-Beckham (6-5 237 pounds) both showed they have the size-speed combination to be a threat vertically at the NFL level, with Strong posting a 4.44 in the 40 and Green-Beckham clocking in at 4.49.

Michigan's Devin Funchess (6-4, 232) is another big target who graded out slightly higher than the other two coming into the combine. He too makes contested catches on tape and can win 50-50 balls downfield, but he didn't run nearly as well as the other two. His 4.7 40 is well below the five-year combine average for receivers. But remember that Funchess weighs 30 more pounds than the average receiver at the combine, so while his speed times did not stack up with some others, they're still solid-to-good for his size.

Lockett is a midround sleeper to watch

Kansas State's Tyler Lockett really impressed today. He's a smaller WR at 5-10, 182 pounds, but showcased his speed with a 4.4-second 40, and did really well in the drills portion. He showed strong hands and was really quick transitioning up the field after the catch. He's a likely third-round pick who can contribute early in his career as a slot receiver and return specialist.