Jonathan Martin went to hospital

Miami Dolphins offensive tackle Jonathan Martin recently checked himself into a South Florida hospital to be treated for emotional distress that led the second-year player to leave the team last week, league sources told ESPN.

Dolphins coach Joe Philbin visited Martin at the hospital, and the organization arranged for his parents to travel to South Florida, the sources said.

Martin's hospital stay was brief before he returned to California with his parents, according to sources.

"He's a strong man. He's doing fine," Martin's father, Gus, told omg! Insider.

The specific treatment of Martin's emotional condition was not disclosed, but sources say it was related to his belief that he had been targeted during a sustained level of harassment from teammates, including suspended guard Richie Incognito.

Martin did not disclose to Philbin any specific incident of harassment or bullying when the coach made the hospital visit, sources said.

The Dolphins suspended Incognito on Sunday night for conduct detrimental to the team after Martin's representatives provided voice mail and text evidence from April that the team agreed was inappropriate.

Martin remains in California, preparing a detailed document for his cooperation with a league investigation into a string of alleged multiple incidents he says led to his emotional distress and exit from the team, sources said.

Some of Martin's former teammates reacted Wednesday to what has become a national controversy.

Indianapolis Colts quarterback Andrew Luck, a teammate of Martin's at Stanford, told ESPN.com that he has talked with Martin.

"I love Jon like a brother," Luck said. "We had a lot of fun -- a lot of good times -- together at Stanford.

"It's obviously an incredibly unfortunate situation. But out of respect for him and what's going on, I'd rather not talk about it."

Pittsburgh Steelers guard David DeCastro, who played on the offensive line with Martin at Stanford, also said he checked in on his former teammate.

"I just wanted to make sure he was OK, and he is," DeCastro told ESPN.com. "I just called him to make sure he was all right."

DeCastro, a first-round draft pick last year, described Martin as a "great player" who he got along well with at Stanford.

"I could care less about football," said DeCastro, who was drafted 19 picks before Martin last year. "I just wanted to make sure he was OK as a person, and he is. So that's good. That's what's important."

Colts tight end Coby Fleener, another Stanford teammate of Martin's, referred to him as a "stand-up guy" and an "awesome character guy."

Three people who know Martin and have spoken to him told ESPN that he wants to continue playing football and has never discussed leaving the sport based on simply playing the game.

Martin's high school coach, Vic Eumont, told the Palm Beach Post that Martin's personality did not fit in with the Dolphins crowd.

Eumont was Martin's coach at Harvard-Westlake School, a private high school in Studio City, Calif. Both of Martin's parents went to Harvard, but Martin passed up on a chance to go to Harvard so he could play football at Stanford.

"Before, he wasn't around Nebraska, LSU kind of guys," Eumont, a former Tulane offensive guard, told the Palm Beach Post. "He's always been around Stanford, Duke, Rice kind of players."

Eumont told the paper he hasn't spoken with Martin since he left the Dolphins last week, but he said he could see how the team might not welcome Martin back in the locker room after Incognito's suspension.

"In locker rooms full of Nebraska, LSU, Southern Cal players, Miami players -- they'll look at this as a weakness," Eumont told the paper. "If he makes it through all this, and if he was encouraged to come back, he'd come back with a vengeance."

Multiple sources confirmed to ESPN on Monday that Incognito used racial epithets and profane language toward Martin on multiple occasions. In a transcript of a voice mail message from April, Incognito referred to Martin as a "half n----- piece of s---."

The NFL is investigating the troubled relationship between Martin and Incognito. One of the pivotal questions being posed by both the league and the NFL Players Association is whether Martin reached out to Philbin as the issues were unfolding.

Sources told ESPN that the NFLPA is calling for a meeting with the agents for Martin and Incognito to discuss how the controversy is damaging both players.

ESPN NFL Insider Adam Schefter, ESPN.com Colts reporter Mike Wells, ESPN.com Steelers reporter Scott Brown and The Associated Press contributed to this report.