Let's get this out of the way first: The Oakland Raiders had a rough 2018 season.

The Raiders went 4-12 in Year 1 of Jon Gruden's second reign as head coach but there's a reason to believe in a quick turn around, according to a few ESPN insiders.

While the Cleveland Browns made arguably the marquee move of the offseason by trading for Odell Beckham Jr., the Raiders made a number of notable additions during the first stretch of free agency. After acquiring star wide receiver Antonio Brown in a trade with the Pittsburgh Steelers, the Raiders bolstered their offensive line by signing left tackle Trent Brown and boosted their secondary by adding Lamarcus Joyner.

Oh, and they also added speedy wideout Tyrell Williams to the mix, as well.

These moves, in the eyes of ESPN's Dan Graziano, Mina Kimes and Mike Sando, place the Raiders as the leader to be the most improved team not named the Browns.

"If Odell Beckham Jr. wasn't the best player to change teams, Antonio Brown would have been," Graziano writes. "Tyrell Williams is a nice complement to him at receiver. Safety Lamarcus Joyner fits a need on defense, which is the side of the ball I expect them to focus on early in the draft. And Trent Brown should be a helpful left tackle. The Raiders might be gearing up for Las Vegas, but the final year in Oakland has a chance to be a lot better than the past two were."

Kimes echoed the belief in a possible Raiders turnaround this season, but she does have questions about the defensive side of the ball.

"I'll go with the Raiders, who added one of the best wide receivers in the league (Antonio Brown) and the most talented receiver available in free agency (Tyrell Williams)," Kimes writes. "I'm worried that new left tackle Trent Brown won't be able to match his success in New England, and there's a ton of work to be done on that defense, but the Raiders undeniably got significantly better last week."

Sando even voted for the Raiders to be more improved than the Browns in 2019, in large part because the Browns went 7-8-1 in 2018 and have fewer things to clean up than the Silver and Black.

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General manager Mike Mayock and Gruden still have work to do to this offseason, but they appear to be on the right track after the first phase of the NFL offseason.