Tyler Skaggs liked to post on Instagram. His last post, on Sunday, was a photo of the Los Angeles Angels, the team for which he was a pitcher — smiling, healthy, young and strong in cowboy hats and boots — outside their jet after they arrived to play the Texas Rangers this week in Arlington, Texas.

Skaggs was pronounced dead in his hotel room in the Dallas suburb of Southlake on Monday, 12 days before his 28th birthday, authorities said.

No cause of death was made public, and authorities said neither foul play nor suicide was suspected.

The Angels' scheduled game Monday against the Rangers was postponed. A memorial sign was raised outside the Angels' stadium in Anaheim, California, as fans gathered to mourn, leaving behind tributes of flowers and stuffed animals.

Steven Beltran adds a memento to a memorial at Angels Stadium in Anaheim, California, for pitcher Tyler Skaggs, who was pronounced dead Monday in Texas. Alex Gallardo / AP

"I'm an Angels fan, an Angels fan. This is tough," Roberto Gutierrez told NBC Los Angeles on Monday. "He was there for us. We've got be there for his family."

Another Angels fan, Steven Beltran, described Skaggs on Monday as a "super nice guy."

"I got a chance to get autographs for my daughter," Beltran told NBC Los Angeles.

Skaggs grew up in the Los Angeles neighborhood of Woodland Hills, and Beltran said: "We joked about the Dodger tattoo on his shoulder. It's just heartbreaking."

I’m still in shock. Just yesterday, Tyler Skaggs was talking about how badly he wanted to pitch at Dodger Stadium in an Angels uniform. One of the kindest, most straightforward people I’ve met in baseball. I’m devastated for his family and teammates. — Fabian Ardaya (@FabianArdaya) July 1, 2019

Just Saturday, Skaggs had started for the Angels against the Oakland Athletics in Anaheim. He pitched well, allowing two earned runs on two hits in 4 1/3 innings, but he took the loss in a 4-0 defeat.

Skaggs was supposed to have been a star after he was chosen 40th in the supplemental first round of the 2009 Major League Baseball draft by the Angels, who soon traded him to the Arizona Diamondbacks. He recorded his first major league win in 2012 after having spent the best part of two seasons in the minor leagues.

We are heartbroken to hear about the loss of a member of our Angels family.



Our thoughts and prayers are with Tyler's friends and family and all of those he touched in our organization. https://t.co/LF2bDFSVgf — Salt Lake Bees (@SaltLakeBees) July 1, 2019

But injuries plagued him throughout his career. After he was traded back to the Angels in late 2013, he underwent ulnar collateral ligament reconstruction on his pitching arm, better known as Tommy John surgery, and missed 19 months, including the entire 2015 season.

Skaggs was able to start 10 games in 2016, and he began the 2017 season as member of the Angels' starting rotation. But then he strained an oblique muscle in his abdomen and was able to make only 16 starts, winning two and losing six. In all or parts of seven seasons in the major leagues, he managed to make only 96 starts, winning 28 and losing 38.

Read Tyler Skaggs' complete career statistics at MLB.com

He had won seven games and lost seven this season at the time of his death. Still, he was highly regarded, seen as a leader in the Angels' clubhouse, and he was expected to have a bright, if belated, future.

Tyler Skaggs walks to the dugout after the first inning of a game against the Chicago Cubs at Wrigley Field in Chicago on April 12. Jon Durr / USA TODAY Sports via Reuters file

"He was becoming a finished product right before our eyes, not just exhibiting immense promise but capitalizing on it," the sports site The Ringer wrote Monday.

The Angels superstar center fielder, Mike Trout, who was a member of the same draft class in 2009, said Monday that he would remember Skaggs as "a great teammate, friend and person who will forever remain in our hearts."

"Words cannot express the deep sadness we feel right now," he said.

Giancarlo Stanton, a Yankees outfielder, posted a lengthy and emotional post on Monday to Instagram about Skaggs' death.

"My message to the angels while having no time for yourself to grieve is to hug each other, laugh, cry," Stanton wrote. "Some Anger will ensue while [you] have to grieve in a fish bowl. A lot will go through your mind. So stay together through that."

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Rob Manfred, the commissioner of Major League Baseball, said in a statement Monday: "I am deeply saddened by today's tragedy in Texas. All of us at Major League Baseball express our deepest condolences to Tyler's wife, Carli, his family, his friends and all his teammates and colleagues of the Angels."