HEADING INTO April's draft, the book on the top two quarterbacks, Jameis Winston and Marcus Mariota, was that Winston, due to his experience in Jimbo Fisher's pro-style Florida State system, was the most pro-ready QB since Andrew Luck. Mariota, many thought, would need time—years?—to get up to speed at the next level after mastering Oregon's spread scheme.

In scouting the two players last year, both in person and during extensive film review, I had little doubt that Winston was the more well-prepared for the NFL. He operated an offense that was very similar to that of most pro systems. And he did so with great comfort and skill. (Of course, he was playing on a talent-laden roster, something the Buccaneers—2--14 last season—lacked.) But I was most dazzled by Mariota's potential, especially if the NFL team that chose him did the smart thing and adopted more spread-offense staples. I thought Mariota, because of his keen mind and rare athletic skill set, was being limited by Oregon's offense and was capable of directing a much more complicated scheme. I believed he would make a much better transition to the NFL than most college spread quarterbacks.

Still. I couldn't have envisioned a debut like this.

With Winston watching from the opposite sideline in the first-ever opening-game matchup between rookie quarterbacks who'd been drafted No. 1 and No. 2, Mariota had the best passing debut in NFL history. In leading the Titans to a 42--14 victory at Raymond James Stadium, he completed 13 of 16 passes for 209 yards and four TDs, adding up to a perfect 158.3 passer rating. Not since Fran Tarkenton launched his Hall of Fame career 54 years ago has the league seen a QB debut like this. Tarkenton tossed four TDs as well, but his final score came in the fourth quarter; Mariota had his quartet (each to a different receiver) by the end of the first half, when the Titans led 35--7 and Winston's Buccaneers were leaving the field to boos.

"Hopefully we'll clean up some of our mistakes."

TITANS COACH Ken Whisenhunt wasn't specifically addressing Mariota in his postgame press conference when he made clear there was room for improvement, but he might as well have been.

For an NFL quarterback the difference between competency and perfection is often an eye movement here or proper foot placement there. And Mariota didn't exactly come charging out of the gate. Tennessee ran a nice, safe play after Sunday's opening kickoff, a naked bootleg pass in the right flat to get the rookie's feet wet. But Buccaneers linebacker Danny Lansanah didn't fall for the run-action fake, and he was steaming toward Mariota as the QB released a poor pass, high and behind running back Bishop Sankey, who couldn't haul it in. A better defense easily could have batted around and intercepted the ball.

Two plays later, though, on third-and-10 from the Titans' 26, with the crowd in a frenzy and Tampa Bay showing blitz—two linebackers threatening the A gap on either side of the center; just one would ultimately rush—Mariota calmly stepped up in the pocket and made the kind of tough throw that many critics said he hadn't shown enough of in college: a 22-yard dart across the middle (just over All-Pro linebacker Lavonte David and away from charging corner Sterling Moore) to tight end Delanie Walker. "He did a lot of things that people questioned he could do, like throw from the pocket," Whisenhunt said afterward. "That first third down—that was a big play."

The Titans didn't draft Mariota just to completely reprogram him, though, and on the next play Whisenhunt lifted straight from the Oregon playbook. The QB rode a handoff to running back Dexter McCluster and, as soon as the Bucs' linebackers bit on the run fake, quickly tossed to receiver Kendall Wright on a backside slant. The receiver snaked through both safeties for a 52-yard touchdown.

Winston's unveiling was less promising. Starting from his 20, he faced a manageable third-and-three, just the way the Bucs had drawn it up after two Doug Martin runs. The Titans brought no exotic coverage or blitz on the play, just straight man coverage underneath two deep safeties. Winston took the shotgun snap, looked at covered tight end Austin Seferian-Jenkins and wisely decided to throw short left to outlet receiver Adam Humphries. But Winston didn't see cornerback Coty Sensabaugh undercutting the route and, under pressure, he threw a soft pass that Sensabaugh turned into a pick-six. "It was just a bad decision," said Winston, who joined the likes of Brett Favre in having his first pro pass returned for a TD.

After staring down a receiver and nearly throwing an interception of his own on his next drive, Mariota converted another tough throw in the seam to Harry Douglas and then made amends for his opening lazy pass by executing the same bootleg to perfection, hitting Sankey in stride for a nearly untouched 12-yard score. With just over eight minutes of game time elapsed, the rout was on.

Whether it was because of the quick deficit or because he was pressured (hurried or knocked down) on each of his first three throws, Winston never seemed to settle down. On his first unhurried pass, a six-yard out to Vincent Jackson with 3:49 remaining in the first quarter, he threw flat-footed to the left, just as he had on the interception. He botched a handoff to Martin two plays later and followed that up with a lucky 21-yard completion to Seferian-Jenkins that was both underthrown and deflected. He threw his first career touchdown (to a wide-open Seferian-Jenkins, against a busted coverage) to make it 21--7, but he hardly looked downfield before tucking the ball and running on both of his subsequent two drop-backs.

This was far from the in-command Winston we saw for much of two splendid seasons at Florida State. As a Seminole, Winston drew raves for his ability to stand in the pocket and allow plays to develop even under intense pressure. There was little of that against the Titans, whose pass rush ranked just 21st in the league last season, according to Pro Football Focus. With two rookies starting on his line and without injured receiver Mike Evans, Winston never looked sure of himself.

That could lead some to wonder whether Winston will be able to deal with true adversity. It's a legitimate question; this Buccaneers team lacks talent in many areas and Winston will be faced with boatloads of hardship. But the answer won't be clear for some time. While the Titans aren't exactly the Seahawks on defense, legendary defensive schemer Dick LeBeau threw enough at Winston and the Bucs to keep them out of rhythm. "Our main thing was to show him different things, make him have to read the coverage," says veteran Titans safety Michael Griffin. "He did the best he could. I don't think he panicked or quit, which is a positive."

Indeed Winston settled as the game went on, throwing for twice as many yards in the second half, securing the ball and upping his passer rating from 56.2 to 85.4. "With time, he'll get better."

"It really couldn't have gone much better for us."

THAT WAS Whisenhunt, standing outside his locker room after the game as Mariota brushed by. The Titans couldn't have scripted a more successful debut for Mariota. Not only did they have the early 14--0 lead, which allowed Tennessee to stay with the ground game (twice as many rushes as passes, for 124 yards), but Mariota also faced a defensive scheme that sits on the endangered species list. The Buccaneers predominantly employ coach Lovie Smith's trademark Cover Two scheme, which can be effective with a talent-laden unit. But that calls for four down linemen who can consistently rush the passer, plus smart and fast safeties. Outside of defensive tackle Gerald McCoy, the Buccaneers don't have any of that. When a Cover Two defense can't generate constant pressure, the zone coverage behind it is easily picked apart by patient and accurate quarterbacks. In other words, this matchup was right up Mariota's alley.

We'll get a better idea of where Mariota is in his development over the next month, as the Titans take on two of the best football minds when it comes to affecting passers (the Browns' Mike Pettine and Rex Ryan of the Bills) plus a Dolphins team that features a formidable defensive line. Some of Mariota's continued issues—staring down receivers, not scanning the field for all of his options, throwing late—could become problematic in those games.

But, at least for one week, this was a big win for Mariota and the Titans' brass, who heard from a chorus of critics warning against drafting a spread quarterback that high in the draft. The Buccaneers were certainly in the large old-school group that echoed that sentiment. "Playing in a pro-style system helped," Smith said of Winston in April after taking the QB No. 1. "We saw him in the same situations you'll see him in the NFL."

Sunday was only one game, and in the end it will be a mere footnote in the careers of both Winston and Mariota. But one of these quarterbacks sure looked ready for his debut. And it wasn't the top overall pick, the one who was thought to be, by far, the more pro-ready of the two.

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Launch Parties

The top five debuts by first-round QBs over the past decade

2015/2 Marcus Mariota TEN 42--14 over TB
13--16, 209 yds, 4 TDs, 0 INTs 158.3
2012/2 Robert Griffin III WAS 40--32 over NO
19-26, 320 yds, 2 TDs, 0 INTs 139.9
2008/3 Matt Ryan ATL 34--21 over DET
9--13, 161 yds, 1 TD, 0 INTs 137.0
2011/1 Cam Newton CAR 21--28 to ARI
24--37, 422 yds, 2 TDs, 1 INT 110.4
2013/16 EJ Manuel BUF 21--23 to NE
18--27, 150 yds, 2 TDs, 0 INTs 105.5
PHOTOPhotograph by Kim Klement/USA TODAY SportsEASY MARCUS Mariota's miracle: throwing more touchdowns in his first pro game (four) than he did incompletions (three). PHOTOWILL VRAGOVIC/TAMPA BAY TIMES/ZUMAPRESS.COMFIRST CRACK Winston's debut started with a whimper: a soft pass (above, left) that Sensabaugh took to the house for a 14--0 Titans lead. PHOTOJIM DAMASKE/TAMPA BAY TIMES/ZUMAPRESS.COM[See caption above] TWO PHOTOSGARY BOGDON FOR SPORTS ILLUSTRATED[See caption above] PHOTO

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