After a tumultuous rookie year and offseason, a professedly reformed Johnny Manziel vowed to make football his priority during his second year in the NFL, and if Manziel's first start of 2015 is any indication, that newfound concentration is doing wonders for the former Texas A&M star.

In a matchup of former Heisman Trophy winners, Manziel and Tennessee Titans rookie Marcus Mariota both flashed the potential that made them star quarterbacks in college. But it was Manziel who stole the show Sunday in Cleveland, completing 8 of 15 passes for 172 yards and two touchdowns in the Browns' 28-14 win.

The performance was bookended by the pair of touchdown passes, both of which went to Travis Benjamin, who also scored on a 54-yarder from Manziel last week against the Jets after Manziel replaced injured starter Josh McCown early in the game.

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The first touchdown this week, on Manziel's first attempt of the afternoon, went for 60 yards and the second, following a lengthy, profanity-inducing scramble on his last pass of the day, went for 50, thwarted a Titans rally and gave Cleveland a two-touchdown lead with just more than three minutes left to play.

The showing was by far the most impressive of Manziel's young career. Last December, he made a pair of uninspiring starts before a hamstring injury ended his season early, and though Manziel performed well early this preseason, a sore elbow led Browns coach Mike Pettine to shut him down for the team's final two tune-up games.

It's far too early to say whether the productive, exciting version of Manziel we saw Sunday is the one we'll see all season, and perhaps it's just as likely Manziel returns to earth next Sunday when the Browns host the Oakland Raiders.

But Cleveland certainly appears to have something promising in the Manziel-to-Benjamin connection that carried it past Tennessee, and for a moribund franchise like the Browns, just having something to be excited about -- and a quarterback with even a little bit of promise -- is a huge upgrade from the revolving door of QBs that has become the norm for fans of the franchise.