(CBS HOUSTON) – Brady Aiken has announced he had Tommy John surgery on Wednesday and is now on the road to recovery.

Aiken wrote a column for The Players’ Tribune on Thursday detailing his post-injury perpective.

The lefthanded pitcher was the Astros’ number-one overall draft pick in 2014, but the two sides could not come to terms on an agreement. The root of the issue seemed to be a concern over Aiken’s UCL in his pitching elbow. As a result of not agreeing to terms, the Astros received the number-two overall pick in the 2015 draft as compensation. Aiken is eligible for that 2015 draft.

Last week, Aiken was making his first start for IMG Academy’s postgraduate team. He had to leave after 12 pitches into his appearance, according to Baseball America.

“When I visited the doctor’s office and got the news I had torn my UCL, I can’t even begin to express how I felt,” Aiken wrote in his column. “I was — and still am — overwhelmed with a lot of different feelings, but mostly it’s disappointment.

“I wanted to let my pitching speak for itself, but now there are going to be new distractions.”

The 18-year-old pitcher also addressed his thoughts on not signing with the Astros.

“I can honestly say I don’t regret not signing,” he wrote. “It was a very difficult decision, but it also was an informed decision based on circumstances only a few people know the truth about. My family and I planned for all the possible outcomes. We weighed the pros and cons, talked with friends and mentors and doctors whose opinions we value and discussed it over a number of family dinners. This wasn’t a decision we made lightly.

“The money wasn’t the only factor to consider,” Aiken added. “I wanted to play somewhere I felt comfortable, with a support system I felt would lay the groundwork for a successful and long career. Making sure I had that in place was worth the frustration of not being able to get on with my career sooner.”

As the initial concerns over the UCL were discovered, the Astros reportedly lowered their signing-bonus offer to Aiken from $6.5 million to $3.1 million. On the last day, that offer reportedly went up to $5 million. Aiken did not sign. Now, he is determined to make it back from surgery.

“I already have a plan in place to rehab my arm, and I plan to come back better than ever,” Aiken wrote. “I also know God has a plan for me. Injuries are part of the job, but so is coming back. I can’t wait to get back on the mound. I can’t wait to compete again.”