Jason Dietrich keeps Cal State Fullerton pitchers on target

Jason Dietrich always wanted to put on Cal State Fullerton pinstripes.

He cheered for the Titans baseball team as a teenager, and visualized himself as a player jogging onto Goodwin Field to an ovation one day.

That dream didn’t materialize. But at 39, Dietrich is finally wearing those pinstripes and has played a major behind-the-scenes role for a Fullerton team that is among college baseball’s best.

As pitching coach, Dietrich guides one of the game’s stingiest — and youngest — staffs. The rotation is headed by two stellar freshmen, Justin Garza and Thomas Eshelman.

Garza and Eshelman, who were getting ready to graduate from high school about this time last year, have a combined record of 24-2, 167 strikeouts and 18 walks in 215 2/3 innings, and an earned-run average of 1.96.

“They are special,” Dietrich said. “A lot of freshmen have trouble adjusting. They just ran with it. The way they go about things, they’re like juniors and seniors.”

How Dietrich would know about juniors and seniors isn’t clear; he didn’t have one in his weekend rotation.

When Fullerton swept through the four-team NCAA regional it hosted last weekend with a 3-0 record, the other starter was Grahamm Wiest, a sophomore who pitched a complete game against Columbia.

Credit goes to Dietrich’s down-to-business, grind-it-out philosophy. That is, basically: changing speeds and spotting pitches around the strike zone, with an emphasis on avoiding walks.

Simple, yet effective.

Eshelman has 78 strikeouts and only two walks in 1072/3 innings. In the deciding game of the regional, a 6-1 victory over No. 24-ranked Arizona State, he gave up one run and six hits in eight innings.

Garza might have been even more impressive in his regional appearance, throwing 81/3 scoreless innings against Arizona State.

The three-game regional totals for the starters: 251/3 innings, two runs, 13 hits, 20 strikeouts, no walks.

Fullerton (51-8) will try to keep it going in a best-of-three-games NCAA super-regional against UCLA (42-17) beginning Friday at Goodwin Field.

As Fullerton’s stock has risen — the Big West Conference champion is ranked No. 5 in the nation — so has Dietrich’s. It just took him a while.

Dietrich pitched two years at Santa Ana College, one year at Pepperdine and five years in the minor leagues. His coaching career began in 1999 at Arcadia High when he took over the pitching staff to help out a former minor league teammate.

From there, he gradually moved up the coaching ladder, from junior college stints at Los Angeles City and Irvine Valley to Division II Cal State Los Angeles before breaking into the major-college level at UC Irvine in 2011.

His first Irvine staff, featuring All-American Matt Summers, had a 2.95 ERA. Then, last year, the Anteaters established a Big West record for fewest hits given up in a season. And when staff ace Andrew Thurman gave up only one run and one hit in eight innings during a series opener last year against Fullerton, Titans Coach Rick Vanderhook took notice.

The Fullerton job opened when Kirk Saarloos left to take a similar position at Texas Christian. Dietrich’s phone rang soon after.

Finally, a chance to wear those coveted pinstripes.

“I hoped that they would call me and ask me to come play here,” Dietrich said. “It wasn’t personal, they just didn’t have any room. So to have that chance to come here 20 years later is a special, special opportunity.

“It’s come full-circle. Like you preach to your players, you expect anything and don’t close the door to it. You want to be noticed, but it’s not always about that.”

Although still in the background, he’s getting noticed now.

andrew.gastelum@latimes.com