What Bears QB Choice Can Say About Rushing Success

New offensive line coach Juan Castillo has a good history with coach Matt Nagy and is being counted on to turn around the run blocking but his most productive years came with scrambling quarterbacks

The amount of faith both Chicago Bears coach Matt Nagy and general manager Ryan Pace have placed in offensive line coach Juan Castillo is staggering.

To turn around a failed running attack, the Bears brought in only Germain Ifedi and a few other backups to bolster their offensive line. The idea is Castillo can coach up the Bears' line in a way Harry Hiestand couldn't in order to make their running game more formidable.

"When it comes down to the word trust with Juan and myself, it's ultimate and I'm just really excited," Nagy said.

The reason the Bears have confidence in Castillo is his past affiliation with Matt Nagy for a brief time in Philadelphia.

"Yeah, for Juan, my history with him goes way back and I just know how he works," Nagy said. "I know how he thinks. And I have ultimate trust in how he's gonna build what he wants to do with that offensive line. Fundamentally he'll have a plan. Schematically he'll have a plan. And then as a teacher and as a friend with those guys, he'll have a plan."

Nagy was a coaching intern two years and an assistant one season while Castillo was offensive line coach, then he was in Philadelphia when the Eagles changed Castillo's job responsibilities in 2011 and 2012.

Castillo's record is solid, although not spectacular. Many of the best rushing seasons Castillo's teams had have been the by-product of a scrambling quarterback and not necessarily the line's productivity.

With the Eagles from 1998-2010 as line coach he only once coached a line when the rushing game averaged below 4.0 yards a carry. However, the best years rushing-wise for the Eagles came when Donovan McNabb was scrambling around and boosting the team's rushing average.

Before McNabb became the starter in 1998 and 1999, Philadelphia averaged 4.2 and 4.1 yards rushing with Castillo as coach. In 2000, McNabb's rushing helped them climb from fourth in the league (4.7) from ninth in Castillo's first two years when Bobby Hoying and Doug Pederson started most of the games. In the only year Castillo coached a team averaging below 4.0 yards a carry, McNabb suffered an injury and Mike McMahon started seven of the games at quarterback.

In Castillo's final Philadelphia season, the Eagles finished first in yards per carry but it was largely because they had moved on at quarterback from aging and injured McNabb to Michael Vick, and it had less to do with the line. 

What can generally be said of those seasons is the Eagles usually rated among the bottom half of the league in rushing attempts under Andy Reid, but they had good productivity. However, the productivity was often the result of a scrambling quarterback. 

It's difficult to say it was entirely Castillo's work because of the running quarterbacks.

It changed in Baltimore and in Buffalo when Castillo worked in those two places as line coach and also running game coordinator.

With a less mobile Joe Flacco at quarterback in 2013, Castillo's first line finished 30th in rushing and dead last in yards per carry at 3.1 yards per attempt. 

However, they rebounded in 2014 to finish ninth in yards per carry at 4.5 before dipping again to finish 24th and 23rd his final two seasons. Flacco was at quarterback almost all the time in those years.

In Buffalo, Castillo benefited again from coaching a line with a running quarterback. Yet, they finished just 18th in yards per carry at 4.1 with Tyrod "T-Mobile" Taylor as signal caller. The next year the running game got an even bigger boost in rushing yards as rookie Josh Allen ran for 631 yards but they averaged only 4.2 yards a carry .

In all, Castillo coached lines for 19 seasons and the teams were below 4.0 yards a carry just three times but in 10 of the 16 other years the running production was greatly aided by a quarterback who scrambled.

What does this suggest about the Bears' offense this season?

Some Bears followers might not want to hear this, but the chances of the Bears enjoying a more productive running attack could hinge on whether they have Mitchell Trubisky at quarterback instead of the less mobile Nick Foles.

In the six seasons when Castillo coached lines not benefiting from a regular, less-mobile quarterback, they averaged 3.1, 4.5, 3.9, 4.0, 4.2 and 4.1 yards a carry. 

While those are much better than what the Bears have done in Matt Nagy's first two seasons as coach, they're nothing close to the production experienced by Castillo teams when they had a quarterback who could move.

Juan Castillo's Lines at Their Best

Year	Team	Yards Per Rush Attempt	Team's QB
2010	Eagles	5.4	Michael Vick
2003	Eagles	4.8	Donovan McNabb
2006	Eagles	4.8	Donovan McNabb/Jeff Garcia
2000	Eagles	4.7	Donovan McNabb
2007	Eagles	4.7	Donovan McNabb/A.J. Feeley
2002	Eagles	4.5	McNabb/Feeley/Koy Detmer
2014	Ravens	4.5	Joe Flacco

The bottom line is the Bears might do somewhat better running the ball with Castillo as offensive line coach but any sizable boost in rushing productivity would be from Trubisky being at quarterback and running the way he did in 2018 when he had 421 yards.

Twitter: BearDigest@BearsOnMaven