As Joseph Randle's life began to unravel early last season, the Cowboys learned that the running back had been betting on sports, according to four sources.

Randle started the first six games in 2015 before his behavior became so peculiar that the Cowboys chose to cut ties with him.

Early Monday morning, Randle was arrested for the fourth time over the last 17 months in Irving on an outstanding speeding warrant out of Coppell. Randle's continued run-ins with the law and his involvement in sports gambling appear to have put his career in jeopardy.

On Nov. 3, a combination of issues led the Cowboys to release Randle. In addition to showing signs of mental instability, he had been involved in placing wagers on sporting events during the 2015 season, sources said.

"All of that became apparent to us right during the season," Cowboys owner Jerry Jones said last week from a Senior Bowl practice in Mobile, Ala. "Not before the season. It became real acute, a combination of things. Some issues ... became more apparent."

Jones was asked if any evidence showed that Randle bet on any NFL games.

"At this time, no," Jones said.

Jones said there's no evidence that shows Randle could have compromised any Cowboys games last season.

"Not to my knowledge, not in any way," Jones added.

Randle couldn't be reached for comment. When contacted, agent Erik Burkhardt said he no longer represents the running back.

NFL spokesman Greg Aiello said Monday that he had no knowledge of an NFL investigation into Randle concerning sports gambling.

"We have never had any information relayed to us alleging that Joseph Randle bet on sports," Aiello added.

The NFL has a strict gambling policy in place for players and other league personnel and has long publicly opposed any form of sports betting.

"There are certain types of gambling that you can't do as a player," Jones said. Referring to the Cowboys, he added: "Obviously you can't be involved in ... anything that we're competing in, and I've never heard of anything like that."

According to league policy, the "NFL opposes all forms of illegal gambling, as well as legal betting on NFL games or other professional, college or Olympic sports. Such activity negatively affects the interests, welfare and integrity of the NFL, its games, clubs, players and coaches, and diminishes public confidence in legitimate sport."

Offers of help

The Cowboys remain concerned for Randle's well-being and believe he needs serious help, a source said. The Cowboys, NFL and NFL Players Association have offered Randle help on several occasions since his release, and he's refused to accept, the source added.

Randle's gambling activity could help explain a mysterious phone call he placed to Irving police during the last week of October, during his final days with the Cowboys.

Randle phoned the Irving police department at 12:35 p.m. on Oct. 28. Department spokesman James McClellan said the running back asked that police go to his home to perform a welfare check on his then-girlfriend, Avina Rodriguez. Randle told police he had found her cellphone in his car and was concerned that someone had broken into his house.

McClellan said Randle met the police at his home and handed over the keys for them to check inside. It turned out Rodriguez was at school. Since there was no suspicion of criminal activity, no report was written up, McClellan said.

Sources said Randle wasn't making sense that day, with his call to the Irving police and wide-ranging stories he told Cowboys officials.

"He admitted to officers that he was having delusions," McClellan said Monday about Randle's police call. "He said that he was delusional, that he was imagining the whole thing."

Randle's last game with the Cowboys was on Oct. 25, a 27-20 loss to the Giants in New York. Randle started the game but pulled himself out in the first series after two carries for 24 yards. Randle, who had been bothered at times in training camp with a strained oblique, came to the sideline and used a stationary bike before having a brief conversation with coach Jason Garrett. Randle then used the stationary bike some more but never went back into the game.

Jones said he's never suspected that Randle pulled himself out of the Giants game for any reason but the injury.

"I've never suspected in any way a relationship between that [and gambling]," Jones said. "I just thought he was [hurt], but I do believe at that time that his entire lifestyle and the whole thing was piling up on him."

Randle was gambling when he was arrested at the Kansas Star Casino in Mulvane, Kan., in late November, three weeks after the Cowboys cut him.

Randle was playing blackjack and became "belligerent" and was "causing problems on the casino floor," according to an incident report. Randle was asked to leave the casino and did so but then returned and argued with security officers before a scuffle ensued. He ultimately was charged with four misdemeanors: two counts of disorderly conduct, one count of criminal trespass and one could of resisting arrest.

Randle was also arrested twice in a four-month span with the Cowboys. In October 2014, Randle was arrested at Stonebriar Mall in Frisco after police said he tried to take a bottle of cologne and a pack of underwear from Dillard's. Randle, who at the time called it "the biggest mistake of my life," received deferred adjudication, and his misdemeanor theft charge was later dismissed.

Randle was arrested again in February 2015 in his hometown of Wichita, Kan., where police responded to a domestic violence call from his hotel room. Randle said the incident stemmed from an argument with his ex-girlfriend, Dalia Jacobs, who is the mother of his toddler son. Randle was cited for marijuana possession, but the drug charge was later dropped.

In April, Kansas authorities said there was a lack of evidence to charge Randle with felony domestic violence after allegations from Jacobs that he pointed a gun at her and her friend.

However, the NFL had investigated the Wichita arrest. One week after the Cowboys cut ties with Randle, the NFL announced it had suspended Randle four games for violating the league's personal conduct policy.

Latest trouble

Randle had been spending time in Kansas before he surfaced locally again Monday. Randle, 24, was arrested at about 3 a.m. in the 1700 block of Finley Road outside the home of Rodriguez and was booked into the Irving jail on a speeding charge.

Randle had an outstanding warrant out of Coppell for speeding in a school zone. He posted bond before noon Monday and was released from custody.

McLellan said Randle showed up at the home hoping to get some sleep before driving back to Kansas. He rang the doorbell but was not welcome there, the report said, and Rodriguez's mother called police. When police arrived, they found Randle sitting in a parked car.

Randle told an officer he was there looking for his car that went missing in Kansas.

"The officer wasn't buying his story," McLellan said. "It didn't make sense."

Randle remains an NFL free agent. League security is keeping close tabs on him, however. Someone with NFL security has already requested a copy of Monday's police report in Irving.

Under the NFL's gambling policy, any violation will be decided by Commissioner Roger Goodell "or his designee on a case-by-case basis. Violations of the policy constitute conduct detrimental to the league and will be subjected to ... such disciplinary action that may include, without limitation, severe penalties, up to and including a fine, termination of employment and/or banishment from the NFL for life."

The final straw came for the Cowboys midway through the 2015 season when they asked Randle to commit to receiving outside help for his unstable behavior and he wouldn't agree to do so, sources said.

"We asked him to do some things that he couldn't do for whatever reason," Jones said, "and that's when we waived him."

Randle was named the Cowboys' starting running back last season after league-leading rusher DeMarco Murray left in free agency to sign with Philadelphia. Despite playing only six games, Randle led Dallas with four rushing touchdowns.

Randle, a fifth-round pick by Dallas in 2013 out of Oklahoma State, was replaced as the starter by Darren McFadden, who went on to rush for 1,089 yards in his first season with the Cowboys.

Jones was asked if the Cowboys made a mistake to rely on Randle as their starting running back to start 2015.

"His situation became more acute during the season than it ever was before the season or last year," Jones said. "We didn't just rely on him. That's why we brought McFadden in. ... McFadden stepped up and did a heck of a job, so I feel like we backstopped ourselves from the standpoint of the team."

As for Randle, Jones added: "I really want him to get straightened around, and obviously he's working on it."

Staff writer David Moore contributed to this report.

Twitter: @DMN_George