Juan Castillo is leaving the Ravens to join the Buffalo Bills Coaching staff

A lot of people were left disappointed when black Monday flew by Baltimore without a single firing or coaching move. The next day turned out to be "retain Tuesday" as Ravens head coach John Harbaugh decided to retain offensive coordinator Marty Mornhinweg and the much maligned defensive coordinator Dean Pees. On Thursday, just two days after the Ravens held their end of the season press conference, the team was very active in the coaching carousel.

First, the team made an expected and long rumored move by hiring former Buffalo Bills and San Francisco 49ers offensive coordinator Greg Roman as the teams new tight ends coach and as senior offensive assistant. In other words, he's plan B just in case Mornhinweg doesn't work out. The Ravens also promoted former tight ends coach Richard Angulo to assistant offensive line coach. The carousel would later continue with a move that is a bit shocking with the departure of a coach who has been part of Harbaugh's staff for the past four seasons and is second only to Pees when it comes to scrutinized coaches. That man is the now former offensive line coach Juan Castillo.

As reported by the Baltimore Suns' Jeff Zriebec, Castillo will leave the Ravens to join the Bills coaching staff that is now led by new head coach Sean McDermott as their new offensive line coach and run-game coordinator. McDermott and Castillo have worked together in the past with the Philadelphia Eagles.

In the four seasons Castillo has been a member of Harbaugh's coaching staff, the offensive line has been a mixed bag and, aside from 2014, the running game has been non-existent. While the offensive line this past season did improve as the season went along, 2014 was the only time when the offensive line actually played at a consistently good level and looked like one of the best offensive lines in the game. Many though will point to Gary Kubiak for the success of the rushing attack and offensive line for that 2014 season. The Ravens rushing offense was ranked 30th in 2013, 26th in 2015 and 28th in 2016.

Even though Castillo's tenure did not live up to expectations, he has done a good job developing players such as Rick Wagner, Ronnie Stanley, Alex Lewis, Kelechi Osemele, and even guys like John Urschel and Ryan Jensen when they came in for an injured starter.

With Castillo now gone and Angulo being promoted to assistant offensive line coach, the Ravens will now be in the market for a new offensive line coach. Whoever the coach is, he will have to be the kind of hire that fits the offensive system and blocking scheme they want to run for the 2017 season. The running game has been made public as the top priority, but the offensive line is just as important and the team has some good pieces along the line with Lewis, Stanley and Marshal Yanda. Re-signing Rick Wagner and finding a center should be at the top of Ozzie Newsome's to do list for the offseason.