Browns quarterback Johnny Manziel will start Sunday's home opener against Tennessee -- and fellow Heisman Trophy winner Marcus Mariota -- because Josh McCown remains out with a concussion.

This will be Manziel's third NFL start. McCown was injured on Cleveland's opening drive last week against the New York Jets. He has not been cleared by an independent neurologist to practice.

McCown had been expected to take part in Friday's workout, and coach Mike Pettine said if he practiced, the 36-year-old veteran would play against the Titans. Pettine is to update on McCowan's status after practice.

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Manziel and Mariota first met when both were recruited at the same time by Oregon. Manziel wound up at Texas A&M, where he became the first freshman to win the Heisman in 2012. Mariota won the trophy last season with the Ducks.

It will be Mariota's second straight matchup against a Heisman winner. Last week, he faced Tampa Bay's Jameis Winston and Mariota threw four touchdown passes in the first half and finished with a perfect 158.3 passer's rating.

Manziel came off the bench after McCown was injured while trying to dive into the end zone in the first quarter. Manziel threw his first career touchdown pass, but also committed three turnovers in a 31-10 loss.

He has shown progress following a rough rookie season, which was followed by him entering rehab for an undisclosed issue.

Manziel's first two starts in 2014 didn't go well. The Browns were beaten 30-0 at home by Cincinnati in his debut and he was injured the following week in a loss at Carolina.

"I'm just trying to go out and play better football than I have in the past," Manziel said this week. "I've been disappointed in the way I've performed, especially ending the season last year. It didn't end on a very good note."

Manziel completed 13 of 24 passes last week for 182 yards. He threw a 54-yard TD pass to wide receiver Travis Benjamin. Manziel also rushed for 35 yards but fumbled twice while scrambling.