SEATTLE -- In the bottom of the first inning Tuesday night, Jack Flaherty walked to the back of the mound at T-Mobile Park and bent down. He scratched in seven letters, and when he was done, he patted the dirt twice, patted his chest twice and pointed to the sky.

Every so often, he glanced at the letters before taking a deep breath and winding into his delivery. He repeated the routine -- pat the mound, pat his chest, point to the sky -- before every inning he pitched in the Cardinals’ 5-4 loss in Tuesday’s series opener against the Mariners.

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The letters spelled out a name: TSkaggs. The gesture was Flaherty’s way of honoring close friend Tyler Skaggs, the 27-year-old Angels pitcher who passed away Monday.

Cardinals manager Mike Shildt said before the game that he had talked to Flaherty about not starting Tuesday in Seattle.

But there was no way that Flaherty wasn’t going to pitch.

“It felt really good to be out there,” Flaherty said. “I felt like that was the only way -- I never felt like taking the night off or pushing it back a day. It just wouldn’t have felt right.”

The Cardinals' right-hander -- who had “RIP TSkaggs” written along the outer part of his cleats -- struggled with command early, but kept the score within striking distance for St. Louis' offense, which tied the game in the seventh on Yairo Munoz’s two-run home run.

Flaherty gave up four runs in 4 2/3 innings while walking four. A 39-pitch second inning when he walked in a run cost him, but he struck out seven.

“Jack gutted it out with a heavy heart,” Shildt said. “He wanted to pitch, and clearly those are tough circumstances. Somebody close to you, he was a big part of Jack’s life, helped mentor Jack to some degree, they were close. That’s got to be -- I couldn’t imagine. That’s a tough thing, especially for a young person.”

Flaherty pitched himself out of traffic on the bases in the first and third innings, as well as struck out two after giving up a two-run home run in the fifth.

“It’s been a long day, but it was about going out and trying to execute for these guys in here, and go as long as I could until Shildt took the ball from me,” Flaherty said. “For most of the game, I felt like I didn’t do the little things right. Shildt let me go out there and continue to fight.”

Flaherty and Skaggs were both California high school products, with Flaherty graduating in 2014 from Harvard-Westlake High School and Skaggs from Santa Monica High School in 2009. They met four or five years ago, Flaherty said, and the two worked out together in the offseason. 

When the Angels were in St. Louis two weeks ago, Flaherty and Skaggs went to dinner to catch up the night before Skaggs pitched against the Cardinals.

Skaggs had mentored Flaherty, 23, but their relationship was mostly a close friendship between two competitors who drove each other to be successful. They talked and shared tips every now and then throughout the season.

“Lot of love for his family, [wife] Carli, just a lot of love for them,” Flaherty said. “He’s an unbelievable person and someone I was lucky enough to know.”