Pitcher Mark Trentacosta is not eligible to pitch for UC Irvine this season.

Pitcher Mark Trentacosta is not eligible to pitch for UC Irvine this season. (Courtesy of UC Irvine / October 2, 2012)

Mark Trentacosta is between a mound and a hard place.

Through no fault of his own and by a convergence of head-scratching rulings, readings and regulations, the UC Irvine senior is a pitcher in name only. But the man without a team has an incredible story, and a cause that will confuse anyone who clings to common sense.

It began last June when the UC Irvine left-hander, who posted a 2.91 earned-run average, won his only decision and struck out 26 in 34 innings for the Anteaters, was drafted in the 34th round by the St. Louis Cardinals.

While filling out pre-draft information cards, routine procedure for teams interested in learning more about prospects, Trentacosta mentioned a slight back strain. The injury was treated by UCI trainers, but was not severe enough to ever keep him from competing. He said any discomfort caused by the injury, which occurred while lifting weights, was gone by the time he finished his college season in May.

Trentacosta, a 6-foot-3, 215-pounder who also pitched successfully for Golden West Community College and Marina High before walking on at UCI, said he agreed to terms over the phone with the Cardinals before they drafted him. It was more of a privilege than a pledge.

"When I was first talking to the Cardinals, I said I'm not looking for money," Trentacosta said. "I just want an opportunity to go out and play [professional baseball]. Whatever you'll pay me, I'll sign for, pretty much."

It was music to any sports executive's ears, but the tune quickly hit a sour note.

Days after the draft, the Cardinals flew Trentacosta to Florida for a physical at their spring training headquarters. He stayed at the team hotel in Palm Beach during his three-night stay.

From Florida, he was shipped to Johnson City, Tenn., where he worked out with the Johnson City Cardinals, a short-season rookie league affiliate. He sat and watched the second day and reported to the clubhouse to prepare for another workout on Day 3.

Before he did anything baseball related that third day, he was summoned to the coaching staff's office. Immediately uplifted by the request, Trentacosta assumed he was being given the go-ahead to begin the career he had always dreamed of pursuing.

But like Crash Davis in a scene from "Bull Durham," Trentacosta was instead notified of his release.

"To be honest, it was probably one of the lowest points in my life," Trentacosta said. "I felt like I'd just gotten into a car accident ... like that slow-motion phase where you don't know exactly what's going on. They told me I had degenerative disc disease. When I first heard that, all I heard was disease and I thought I was dying. It was a little hard to swallow."

Trentacosta was given a plane ticket home, having not accepted a dime in salary or even signing a contract with the Cardinals.

He was also sent home without answers as to why he had been released, only a cryptic reference to the trainer by one of his Johnson City coaches.

He was later given his MRI results and after a few weeks, was able to contact the team doctor who, without ever talking to him, Trentacosta said, had included " shooting pain down my left leg," in his report. There was never such a pain, Trentacosta said.

Trentacosta said he was examined upon returning home by a chiropractor with vast experience dealing with athletes. The chiropractor said the MRI did not reveal anything more than what might be found in two-thirds of the players on any given baseball team.

Trentacosta began looking for a second opinion from a medical doctor or an orthopedic surgeon. But not before looking for a second chance.

He began talking with scouts from other major league teams, hoping to sign as a free agent. But he learned, after inquiries to the MLB commissioner's office and the scouting bureau, that he was forbidden from signing elsewhere, at least until the 2013 draft.

"I was told that the Cardinals owned my rights and if other teams talked to me, they could face sanctions," Trentacosta said.

His focus then shifted to returning to the college game, but after conferring with NCAA compliance officials on the UCI campus, he learned that his stay in Florida exceeded the allowed 48-hour window to have expenses covered by the professional team. He would have to repay the additional hotel, food and transportation expenses paid by the team if he wished to retain his NCAA eligibility.

That amount proved prohibitive, said Trentacosta, who fielded advice about perhaps playing at an NAIA school, where he would be eligible. But, only 10 units away from his bachelor's degree in sociology with a minor in education, he has elected to finish at UCI, from which he will graduate after the fall quarter.

"When I was in high school, all my dreams were to be a high school math teacher and baseball coach," said Trentacosta, who is planning to be married in November, 2013. "This has definitely taught me that nothing comes easy in life. It has definitely given me a wake-up call and told me I need to grow up and that not everything is rainbows and happiness. With everything that's happened, I've seen how baseball can be taken away. Once I get my degree, no one can take that away from me."

Trentacosta said he still plans to keep his arm in shape, just in case he gets another opportunity in professional baseball.

"Baseball is definitely something you can't take for granted," he said. "You need to go out there and have a good time [playing]. You never know when it's going to stop and you might not be able to pitch again, when something like this happens and it's taken away from you by something not under your control.

"When they told me I was going home, I thought my baseball career was just over. I didn't think anybody would want me, because I was damaged goods. Then, I started talking to [baseball] people and I started getting hope. But then, it was like when you take the training wheels off a bike. You start riding, then you fall back down again. That's kind of how I felt when I was told I would have to wait until next year."

barry.faulkner@latimes.com

Twitter: @BarryFaulkner5