BEREA, Ohio -- On their opening series in Sunday's game against the Chicago Bears, the Cleveland Browns faced third-and-10. Yet after misfiring toward him the previous play, quarterback Baker Mayfield sought out receiver Odell Beckham Jr. again.

Only this time, the two were completely in sync.

As soon as OBJ made his cut, Mayfield fired a strike to the spot Beckham would end up in, resulting in a seamless 13-yard completion and a first down.

The connection set the tone for the rest of the afternoon -- and potentially the rest of the season -- as the duo hooked up for five receptions off nine targets for 77 yards in a solid season debut.

“Absolutely,” said Beckham, when asked if he felt like he had a rapport working with Mayfield in his first game back since the season-ending knee injury in Week 7 of last year. “Got my feet wet. Glad to get that one out of the way.”

Coming into this season, Mayfield and Beckham had notoriously struggled to get on the same page. In fact, over their first two seasons together, they owned the second-worst completion rate (54.6%) of any quarterback-receiver duo in the NFL, with a minimum of 150 attempts, according to ESPN Stats & Information.

Yet despite Beckham being a limited participant in practice throughout training camp and the first two weeks of the season, he and Mayfield piled up reps together in the offseason. That started over the summer, when Beckham flew to Mayfield’s hometown of Austin, Texas, and continued through the preseason, when they constantly worked together on passing routes off to the side during practices.

Sunday, all of that seemed to pay off, as the two flashed a chemistry that stood in contrast to their past issues.

Later in the third quarter, the Browns once again faced third-and-long. Once again, Mayfield and Beckham were on the same page, connecting on a back-shoulder throw along the sidelines for a 26-yard reception and another first down. The pass set up a field goal, allowing the Browns to take a 13-3 lead, putting them in command over the Bears the rest of the way.

“That battery has thrown a lot of balls together,” Browns coach Kevin Stefanski said. “You see that work they’ve put in show up on Sunday. That’s the type of thing you need in the pass game. In order to have precision in the pass game, everyone has to be on point.”

Sunday’s on-point performance should give Mayfield and Beckham plenty to build on, especially as Beckham regains his conditioning.

Beckham played 52 of Cleveland’s 81 offensive snaps in his first game back. In addition to the five catches, he also had a 10-yard rush off a reverse. But despite that being a tick below his average play load since joining Cleveland (56.3 snaps per game), Beckham said afterward he was “exhausted.”

“I just felt like I could never get my legs underneath me,” he said. “I came out and tried not to go crazy in warmup or anything. But got to the game, and I swear I just felt like each play I could not get them underneath me.”

As Beckham reacclimates, he’ll be able to rediscover his legs. And if Sunday was any indication, he and Mayfield just might be on their way to uncovering an uncoverable connection.