(CNN) As recently as June, Baylor University's football coaching staff seemed hopeful that defensive end Sam Ukwuachu would finally be taking the field for the Bears.

He would add depth to the defense for a team trying to reach the College Football Playoff after narrowly missing last year.

Instead, Ukwuachu was sentenced to six months behind bars and 10 years probation, according to CNN affiliates KTWK and KETK , for sexually assaulting a fellow Baylor student in 2013.

Much of this case remained a mystery until this month. In fact, the media and public had no idea this football player in a major program was even in trouble with the law.

It seemed that few knew he was in any legal trouble until an article earlier this month in the Waco (Texas) Tribune-Herald.

Sexual assault case initially stalled

Until the facts came out at trial this week, no public details were made available of what happened on homecoming night in October 2013. The woman, then a soccer player for Baylor, testified that she met Ukwuachu through the Baylor athletic tutoring program, the Waco paper reported. According to Texas Monthly, the woman testified that after agreeing to get something to eat or go to another party, he instead drove her to his apartment. She testified that the sexual assault took place in the bedroom.

Waco police interviewed the woman and filed a report but suspended the case. No arrest was made. CNN has reached out to Waco police but has not yet heard back. Baylor Associate Dean Bethany McCraw testified that "there was not enough evidence to move forward" in the school's investigation, according to the Waco paper.

The case was forwarded to the district attorney's office in March 2014. In June 2014, prosecutors received an indictment.

Before the trial, Ukwuachu's attorney Jonathan Sibley told the Waco Tribune-Herald that his client and the woman had a prior relationship and that the encounter was consensual.

"We are looking forward to the trial," Sibley told the newspaper. "Sam passed a polygraph exam, he's been cleared by Baylor and has graduated and is 100 percent innocent of these charges against him. He has done everything a man can do to clear his name, and he is looking forward to the trial so he can finally do that."

Previous red flag?

Before transferring to Baylor, Ukwuachu was named a freshman All-American when he was at Boise State University in 2012. That season, he had played in all 13 games for the Broncos, starting 12 of them. He sat out as a true freshman in 2011 and was redshirted.

In May 2013, Boise State announced that Ukwuachu was dismissed from the team for violating unspecified rules. No other details were made available.

According to records cited by the Waco paper, when Ukwuachu was at Boise State, he allegedly attacked his girlfriend while drinking and using drugs. The newspaper said records show that Ukwuachu broke a window and cut his arm, which led to a Boise police investigation. It's unclear if this incident led to Ukwuachu's dismissal from Boise State. CNN has reached out to the university but has not yet heard back.

At the trial this week, that former girlfriend in Idaho told the jury that Ukwuachu punched her in the head several times and choked her, the Waco Tribune-Herald reported. Ukwuachu denied the allegations.

The following month after he left Boise State, Ukwuachu told the Waco paper that he was transferring to Baylor. He declined to discuss his dismissal from Boise State.

"It was a personal issue that I don't want to go in depth with," Ukwuachu told the newspaper at the time. "But it wasn't a big issue. A minor problem occurred and the coaches decided I needed to get a fresh start with somebody else."

Baylor coach expected Ukwuachu to be back

Ukwuachu would have had two years of eligibility remaining had he played for Baylor. However, he never played a down for the Bears.

In 2014, he was suspended from the team, but reasons weren't given as to why, according to the Dallas Morning News . However, recently there were expectations from Baylor that Ukwuachu might take the field for the Bears for the 2015 season.

This is even despite his indictment in June 2014. The player's attorney, Sibley, told the Waco paper that Baylor would not let Ukwuachu play in 2014 once he was indicted but that he should be allowed to play if he were acquitted.

"Ukwuachu is a guy we're expecting to be back," Baylor defensive coordinator Phil Bennett said in June, a year after the indictment, according to the Dallas paper. "We expect him to be eligible in July. That gives us probably five or six guys we can play at end."

But all of that changed. Ukwuachu eventually was dismissed from the Baylor football team for violating unspecified rules, CNN affiliate KWTX-TV in Waco reported . Ukwuachu graduated from Baylor in May and was taking graduate courses before the trial. He still had a year of eligibility to play football after graduation, according to NCAA rules.

Report: Judge found Baylor investigation insufficient

According to Texas Monthly , Assistant District Attorney Hilary LaBorde told 54th District Judge Matt Johnson that Baylor's investigation consisted of interviewing Ukwuachu, his accuser and one friend of each. The article also said that LaBorde said that the school never saw the rape kit collected by the sexual assault nurse examiner. Texas Monthly reported that the judge sustained a motion from the prosecution that restricted the defense from referring to the Baylor investigation during trial because it was so insufficient.

The Waco Tribune-Herald reported that McCraw, the Baylor associate dean, testified that she did not review the nurse's report or review Boise State disciplinary records before making her determination in the investigation.

Following Ukwuachu's conviction, Baylor released a statement that "acts of sexual violence contradict every value Baylor University upholds as a caring Christian community." The school outlined steps taken there, such as staffing a Title IX office with two full-time investigators and supporting sexual assault survivors.

Baylor followed up Friday by stating that, after a meeting that afternoon, President and Chancellor Ken Starr ordered "a comprehensive internal inquiry into the circumstances associated with this case and the conduct of the offices involved." That review will be led by Jeremy Counseller, a law professor and former prosecutor.

"After analysis of his report, President Starr will determine what additional action may be necessary," the Waco school said.

Second chances not uncommon

Baylor head coach Art Briles said Friday that he was not aware of Ukwuachu's past . However, Texas Monthly obtained court documents saying that Boise State and Baylor had some communication regarding Ukwuachu. The documents also said that Boise State officials expressed reticence about supporting Ukwuachu's efforts to play again, the magazine said.

According to the Waco paper, after the news of Ukwuachu's charges finally came to light more than a year later, Briles told reporters , "I like the way we've handled it as a university, an athletic department and a football program."

Chris Petersen -- now the head coach at the University of Washington -- was Boise State's head football coach when Ukwuachu was a member of the Broncos. In a statement Friday, he said he had reached out to Briles about Ukwuachu transferring.

"After Sam Ukwuachu was dismissed from the Boise State football program and expressed an interest in transferring to Baylor, I initiated a call with coach Art Briles," Petersen said in the statement. "In that conversation, I thoroughly apprised Coach Briles of the circumstances surrounding Sam's disciplinary record and dismissal."

This case isn't the first example of a university bringing on a college football player with a checkered past. Recently, University of Alabama head football coach Nick Saban took a chance on Jonathan Taylor, who had domestic violence issues when he was at the University of Georgia.

"As I noted in my comments when the decision was made to allow Jonathan Taylor to attend the University on a football scholarship, I believe in second chances," Alabama Director of Athletics Bill Battle said in a statement in March when Taylor was dismissed.

"I still do. However, being successful in that second chance requires responsibility and accountability. In Jonathan's situation, the University and the Department of Athletics set forth very clear standards of accountability and expectations of conduct. Jonathan was afforded a chance to successfully overcome the difficulties that resulted in his departure from the University of Georgia. Unfortunately, it appears that he was unable to do so, in spite of extensive efforts to assist him."