The Pittsburgh Pirates led the major leagues with 20 shutouts this season. Pretty impressive for a team with a 71-91 record.

The Pirates finished seventh in MLB with a 3.76 ERA, the highest they have ranked since being fifth in 2015. Again, impressive for a last-place team.

The Pirates' ERA also improved four years in a row for the first time in franchise history.

It is not a reach to say the Pirates would have lost at least 100 games if it weren't for their pitching staff's outstanding performance. After all, the Pirates were last in MLB in runs scored and home runs under first-year hitting coach Matt Hague.

So, the news that pitching Oscar Marin is going to be fired by the Pirates after six seasons on the job is quite surprising. He would seem to be the last person to be the fall guy for the Pirates' seventh straight losing season and 29th in the previous 33 years.

Yet Marin is walking the plank – pardon the cheesy pirate reference – after his best season. The Pirates have yet to confirm the news, so no reason has been given for the move. However, it makes little sense.

Most of the Pirates' young starting pitchers have made progress under Marin's tutelage.

Paul Skenes was the National League Rookie of the Year last season. He is the heavy favorite to win the NL Cy Young Award this season after posting an MLB-best 1.97 ERA in 32 starts, belying his hard-luck 10-10 record.

Rookies Bubba Chander and Braxton Ashcraft were impressive and should be long-term fixtures in the rotation. Mike Burrows, another rookie, improved as the season went on.

Marin was close with former Pirates manager Derek Shelton, who was fired on May 8 as Don Kelly was promoted from bench coach.

Whether Marin's relationship with Shelton led to the move is unknown. Third base coach Mike Rabelo, also expected to be fired, was also close to the former manager.

So maybe there's a trend.

Yet, it's spitballing because there are no factors on the surface that adequately explain Marin's firing.