OL Kelechi Osemele is about to sign a huge $60 million deal with the Raiders

Despite offering offensive lineman Kelechi Osemele what Ravens head coach John Harbaugh described as an "aggressive deal," NFL Network's Rand Getlin is reporting that Osemele has agreed in principle to a massive five-year, $60 million deal with the Oakland Raiders. He'll officially sign on Wednesday when the new league season gets underway.

Although Harbaugh made it clear that he wanted to retain Osemele, the 26-year-old decided to test the free agent market. Based on his performance in Baltimore and his versatility at both tackle and guard, Osemele was considered one of the best linemen to hit the open market this season.

Osemele, the top offensive lineman in our free agent rankings, will help protect young quarterback Derek Carr and boost a running attack that finished 24th in the league, according to Football Outsiders.

Osemele was considered a possibility to receive the franchise tag from the Ravens before they used it on kicker Justin Tucker. The projected number for offensive linemen this season is $13.5 million, which is an awful lot to pay an interior lineman. However, the Ravens gave Osemele an opportunity to play left tackle in four games last season, and they were pleased with the results.

Baltimore intended to move on from Eugene Monroe and transition Osemele to that position, which would have justified a significant pay raise. Osemele, playing on his rookie deal, had a base salary of just $846,255 in 2015.

Since being drafted by the Ravens with the 60th overall pick in the 2012 NFL Draft, Osemele has started 51 of 64 regular season games, including 14 games in 2015. He missed seven games in 2013 after landing on injured reserve with a back injury that required surgical repair.

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