SaberCats fullback Johnie Kirton was found dead in a Santa Clara hotel room Monday night, leaving his Arena Football League teammates shocked and struggling for answers.

“Nobody knows much at this point,” said Mark Grieb, the team’s star quarterback. “We’re just stunned. One minute you’re playing with a guy and then the next you hear that this has happened. He was such a good guy who really fit in well with the team.”

Kirton, 26, a native of Everett, Wash. who played collegiately at the University of Washington, was a newcomer to the SaberCats. The team had acquired the 6-foot-3, 290-pound fullback from the rival Arizona Rattlers on May 9.

He had made an immediate impact on the field, scoring five touchdowns in the two games he played with San Jose. Just Saturday night, Kirton has scored three touchdowns — including the game-winning score in overtime — as the SaberCats defeated the Chicago Rush, 84-77.

“He was such a great kid, and in the short time he was in San Jose he was such a valued member of our organization’s family,” said team co-owner and coach Darren Arbet in a statement. “Johnie was a great team guy and hard-nosed player, and he will be sorely missed.”

Grieb said a teammate discovered Kirton’s body after a receiving a call from the player’s girlfriend. She was concerned that she couldn’t reach Kirton and asked the teammate to look in on him.

Santa Clara police Capt. Phil Cooke said they received a call to a Santa Clara hotel room shortly after 11 p.m. Monday where they found an unidentified man dead. Cooke said he would not speculate on the person’s identity until it was confirmed, but that there was no reason at this point to suspect any crime had been committed in connection with his death.

“It’s a tough situation because he just came here two weeks ago,” Grieb said. “But it’s like one of my teammates said, you could just tell that he had a kind heart.”

Kirton, Grieb added, has a young daughter, “and that just makes this even worse.”

He was the Gatorade State Player of the Year in Washington in 2003 when he rushed for 2,675 yards as a high school senior. With the Huskies, he first played tight end and then defensive tackle. As a senior captain in 2008, he played 12 games, making 27 tackles, including two for a loss, and a sack.

After playing in Arizona as an AFL rookie in 2010, he spent the 2011 AFL season with Chicago where he broke four team records, including rushing yards in a season. He had returned to the Rattlers this season, playing two games before being traded to the SaberCats.

“My love of the game is still there,” Kirton told the Ahwatukee (Ariz.) Foothill News earlier this month. “I’m playing it because I love it.”

Kirton also had worked for the Kyrene School District in Tempe, helping run an after-school program called the Road Crew.

“I just try to find ways to keep their attention and interest,” Kirton told the newspaper. “Growing up as the oldest of nine children, I was a natural leader just because the other kids looked up to me. That is how I will relate to these kids.”

Arbet cancelled the team’s practice Tuesday, but many team members still gathered at the SaberCats’ training facility in Sunnyvale so they could mourn together. Grief counselors also were going to be made available for anyone who wanted to talk, Grieb said.

The team plans to honor Kirton by wearing helmet stickers bearing his number 37 at their game Saturday against the Milwaukee Mustangs.