Johnny Manziel runs with the ball in the Browns’ preseason opener at Detroit. (Rick Osentoski/AP Photo)

The Cleveland Browns enter preseason Round 2 of their quarterback competition with rookie Johnny Manziel already having captivated the football-watching public, but yet to secure the starting job for the regular season over Brian Hoyer.

Manziel can take a significant step toward winning that job if he performs well when he splits the snaps with Hoyer on the first-team offense Monday night at FedEx Field. Hoyer is scheduled to start when the Browns play the Washington Redskins in their second game of the exhibition season, but Manziel is expected to get equal time with the starting offense.

The Browns’ competition, thanks to Manziel’s presence, remains the league’s most compelling preseason quarterback duel. But there are others, notably with the New York Jets and Minnesota Vikings, and decision time is nearing. The third preseason game is traditionally when coaches put their starting players on the field for the longest stretch as the dress rehearsal for the season, before generally sitting out the starters in the Week 4 finale of the exhibition season to avoid injuries.

The brightest spotlight will be on Manziel as he tries to prove he’s ready to be a starter entering his rookie season.

“I think luckily for me there’s three more games for me to get out there and learn, continue to go through certain situations versus different defenses … and just growing up as a quarterback,” Manziel said after making his NFL preseason debut last weekend in Detroit. “That’s what I need to do.”

Manziel already has demonstrated he’s one of the sport’s biggest attractions. The Browns-Lions game drew an average of 2.82 million viewers on the NFL Network, making it the highest-rated preseason game ever on the league-owned television channel by a margin of 36 percent.

Now he must show there’s substance to go with the eye-catching style. Manziel’s performance in his unveiling against the Lions was far from dominant. He missed some reads in the passing game and the Browns managed only a single field goal in the four drives he led, not counting a possession at the end of the first half that consisted of merely a single-play kneel-down.

But Manziel also showed promise during his outing at Ford Field. He connected on seven of 11 passes. He seemed to grow increasingly comfortable in the pocket as the game progressed. And with first-year Browns offensive coordinator Kyle Shanahan employing a scheme for Manziel similar to what he used with the Redskins in 2012 when quarterback Robert Griffin III was a rookie — complete with the pistol formation and option plays — Manziel ran for 27 yards on six carries.

“I think I just need to continue to do what these coaches are asking me to do, continue to learn and go through these situations in these games and try and handle them the best that I can while they’re coming at me,” Manziel said after the game in Detroit. “I’m sure there will be these next few weeks adversity that I’ll have to overcome. But at the same time, that’s part of this game. I need to continue to try and handle those situations the best that I know how, and try and put this team and my group — whichever the ones, the twos, the threes, the fours, whatever it is — try to move the ball down the field and help our team win a game.”

Hoyer clearly is the “other” Browns quarterback in the public’s view. Coach Mike Pettine even fielded questions from reporters in recent days about whether Hoyer would be expendable or might be traded if Manziel wins the starting job. The Browns just signed veteran quarterback Rex Grossman, who previously was with Shanahan with the Redskins.

“I’m just trying to worry about what I can control,” Hoyer said after completing six of 14 passes for 92 yards in the preseason opener while directing the Browns to two field goals on three drives, “and that’s my play.”

New York Jets: Geno Smith vs. Michael Vick

Geno Smith appears to have the Jets starting QB job within his grasp. (Elsa/Getty Images)

The Jets play Saturday night at Cincinnati with Geno Smith perhaps close to being named the team’s starter ahead of Michael Vick. The Jets haven’t made anything official, but it appears increasingly likely Smith will be the starter and Vick will be an insurance policy, ready to take over if Smith stumbles.

Smith started all 16 games last season as a rookie but threw 21 interceptions to go with 12 touchdown passes and had a passer rating of 66.5. When Vick was signed in the offseason, there was speculation a down-to-the-wire quarterback competition was in store. But as it turned out, the job seemingly has been Smith’s all along. Vick could begin the season as a situational quarterback, perhaps going into games when the Jets want to utilize his running skills. But he probably will back up Smith and be ready to step in as the starter if needed.

Minnesota Vikings: Matt Cassel vs. Teddy Bridgewater

The Vikings host the Arizona Cardinals Saturday night, coming off a preseason opener in which Matt Cassel outplayed rookie Teddy Bridgewater. Cassel completed 5 of 6 passes for 62 yards against the Oakland Raiders, while Bridgewater connected on only 6 of 13 throws for 49 yards. Bridgewater probably will have to play much better in this game to be even a consideration for the Vikings as a possible season-opening starter.

Bridgewater was taken with the final pick of the first round in May’s NFL draft, and some talent evaluators around the league say he will be fine if too much isn’t expected of him too soon.

“People need to not get carried away,” one NFC front office executive said recently. “He wasn’t a top-five or top-10 pick. He doesn’t have a team around him like [Seattle’s] Russell Wilson has. He does have [Vikings tailback] Adrian Peterson there. Give him some time and he’ll be okay. By the end of the season, he’ll be their best quarterback. Maybe not right away but by the end of the season.”

Jacksonville Jaguars: Chad Henne vs. Blake Bortles

In Jacksonville, the Jaguars have remained adamant Chad Henne will be their starter and prized rookie Blake Bortles will wait his turn to play.

Bortles was the third overall selection in the draft and he has been impressive in his two preseason games. He completed 11 of 17 passes for 160 yards Thursday night against the Chicago Bears. That came after a 7-for-11, 117-yard debut against the Tampa Bay Buccaneers. But the Jaguars have preached patience with Bortles while Henne, a former starter in Miami, is to serve as a caretaker of the starting job. The Jaguars don’t want to rush Bortles into the starter’s role too soon and have risk having him suffer a career setback. Bortles has looked capable of entering his rookie season as a starter, but it would take an abrupt change in stance by the team for that to happen.

History says Bortles is likely to get his chance at some point this season. According to ESPN, the only three quarterbacks taken in the top five of the NFL draft since 1970 who failed to make a single start as a rookie were Art Schlichter, Carson Palmer and Philip Rivers.

Oakland Raiders: Matt Schaub vs. Derek Carr

Rookie Derek Carr likewise has remained behind starter Matt Schaub in Oakland even after Schaub completed only 3 of 7 passes for 21 yards against the Vikings in the preseason opener. The Raiders host the Lions on Friday night.

Schaub is coming off a 10-touchdown, 14-interception season in Houston. The Raiders hoped the change of scenery might do him some good and help him more closely resemble the quarterback who had a passer rating above 90 for five straight seasons for the Texans between 2008 and 2012. But if he doesn’t turn things around quickly, it’s difficult to envision the Raiders sticking with him as the starter too far into the regular season.