For the second time in five years – and again after a regular-season loss to the Washington Redskins – Ravens coach John Harbaugh has decided to fire his offensive coordinator in an effort to jumpstart a struggling unit.He can only hope today's decision works as well as it did in 2012.The Ravens fired offensive coordinator Marc Trestman Monday, a day after the play caller curiously abandoned a productive running game during a 16-10 loss to the Redskins.Trestman, who replaced Gary Kubiak after the 2014 season, lasted all of 21 games as the Ravens' offensive play caller.Quarterbacks coach Marty Mornhinweg, a former offensive coordinator of the San Francisco 49ers, Philadelphia Eagles and New York Jets and head coach of the Detroit Lions, will take over as the play caller. He'll become quarterback Joe Flacco's fifth offensive coordinator in as many seasons."After very careful consideration, I have decided to make a change to our offensive coaching staff and have replaced Marc Trestman with Marty Mornhinweg as offensive coordinator for the rest of the season," Harbaugh said in a statement. "My obligations are to the team, the organization and the fans to be the very best team we can be. Today we find ourselves one game out of the division and conference lead after experiencing two tough losses at home. We will work to be better in every aspect of our football team. Our expectations are high, and we look forward to fulfilling them.""I appreciate and respect the efforts and contributions Marc has made to the team since his arrival. Marc is a good person and an excellent football coach."The turnover at offensive coordinator started with Harbaugh's decision to fire his longtime play caller Cam Cameron in December 2012 after a 31-28 overtime loss to the Redskins. The Ravens were 9-4 at the time and in first place in the AFC North. Jim Caldwell's ascension into the offensive coordinator role was ultimately viewed as one of the key moves in the Ravens' Super Bowl run as Flacco played the best football of his career.Today's decision to fire Trestman, the former head coach of the Chicago Bears, was less surprising than the Cameron move. The frustration in the locker room about the offense's struggles was palpable following Sunday's loss to the Redskins, which drops the Ravens to 3-2 after a 3-0 start.Harbaugh did not criticize Trestman on Sunday, but he did say, "I think we have to find our offense. We've had that all year, basically. That's been the story of the season. We can't find continuity on offense."Flacco, meanwhile, seemed to be as frustrated as he's been in a long time."I'm not going to get into all that," Flacco said, when asked if he felt changes needed to be made. "We're not playing well enough. We're not making plays. … We are running off the field way too much."Against the Redskins and their 30th-ranked run defense, the Ravens ran the ball 11 times for 74 yards in the first quarter. However, the next three quarters, they had only seven more designed runs. Flacco threw the ball 46 times a week after throwing 52 passes in another close loss to the Oakland Raiders.Trestman came to Baltimore with a reputation as a pass-first offensive coordinator, and he lived up to that. The primary complaint about his play calling was he abandoned the run too quickly. Last year, the Ravens set a franchise-low with 383 rushing attempts. Their offensive line struggled to run block last year and the Ravens fell behind regularly during a 5-11 season, which often forced Trestman's hand.The Ravens' offense finished last season ranked 14th in total offense, tallied the second most net yards (5,749) in franchise history and set a franchise record by averaging 266.9 passing yards per game. But it was impossible really to evaluate the job Trestman did as the Ravens started four different quarterbacks and had significant injuries to many of their prominent offensive players.This year began with high hopes as the Ravens boasted of having as much depth at the skilled positions as they've had in a long time. However in three of their first five games, the Ravens have managed just one offensive touchdown. Whether it was a struggling running game, a lack of big plays down the field or a flurry of penalties, the offense has been its own worst enemy so far.And Trestman ultimately paid the price.