The Arizona Diamondbacks starting rotation has gone from having the worst ERA in baseball (5.19) in 2016 to the second best ERA in 2017 (3.49).

The pitchers have to execute — but team President and CEO Derrick Hall said the catching trio of Chris Herrmann, Chris Iannetta and Jeff Mathis deserve a lot of praise for the rotation’s turnaround.

“The pitchers have kept us in every game this year,” Hall told Doug & Wolf on 98.7 FM, Arizona’s Sports Station. “I give a lot of credit to Chris Herrmann and the catchers as well. Jeff Mathis has been phenomenal all year, he gets hurt, Chris Iannetta and Chris Herrmann have stepped up.

“Herrmann has really been more or less, (Patrick) Corbin’s pitcher every time he goes out to get him back on track. These guys are calling great games, they are pitch frames. I mean, it is phenomenal what they have done night after night.”

After the San Diego Padres blasted Corbin for eight runs in less than four innings on Sept. 8, Herrmann and Corbin went to the slider often early in the game and that helped him bounce back with 6.2 innings of one-run ball against the Colorado Rockies Wednesday.

In 39 games (30 starts) this season, Herrmann has a catchers ERA of 3.01, the best among the Diamondbacks backstop trio. In 69 games (61 starts), Iannetta has a 3.96 ERA and the now-injured Jeff Mathis posted a 3.55 catchers ERA in 56 games (55 starts).

Herrmann’s sample size (274.2 innings) is significantly smaller than Iannetta (559.2) and Mathis (466.2), but Corbin and him have worked well together in the second half.

Compare that to last season and the difference is astonishing. Welington Castillo played in 107 games (103 starts) last year and had a 5.04 catchers ERA. Herrmann played in 31 games (29 starts) and had a catchers ERA of 4.34.

Hall also said general manager Mike Hazen deserves a lot of credit for changing the organization’s philosophy on the catching position.

“Hazen told us that when we interviewed him,” Hall said. “One of the first things he said, ‘you know I haven’t had a whole lot of time with the Red Sox in the playoffs to analyze your entire staff and your entire roster. However, I can tell you we’re going to have to get defensive minded at catching and we’re going to have to make some changes, and that is one of the first things he did.”

Hazen’s decision sure has paid off and should help the Diamondbacks secure a playoff spot.