Bryan Woo injury update: Mariners starter dealing with pec muscle inflammation after leaving start vs. Astros

Seattle Mariners right-hander Bryan Woo has been diagnosed with minor inflammation in his pectoral muscle, according to what manager Dan Wilson told reporters ahead of Saturday's game versus the Houston Astros. Woo underwent imaging after departing Friday's start before he could officially begin the bottom of the sixth inning.

Wilson noted that the Mariners remain uncertain if Woo will require a stint on the injured list -- and that they'll need another 24-48 hours before they can make a call. That won't be a light decision because players who are placed on the IL during the regular season must serve their full stint before they're eligible to return for the playoffs.

"I just felt a little tightness," Woo said on Friday. "I tried to come out and throw that sixth and didn't feel like it was best for the team. I felt like [Bazardo] was ready to go. We'll get some stuff done tomorrow, and I'll know more. I really don't know much so far."

Woo, 25, has developed into a reliable starter for the Mariners. In 30 appearances this year, he's amassed a 2.94 ERA (129 ERA+) and a 5.50 strikeout-to-walk ratio. His contributions have been worth an estimated 4.3 Wins Above Replacement, per Baseball Reference's calculations. Earlier this summer, Woo was honored by being named to his first career All-Star Game.

At one point this season, Woo had completed at least six innings in 25 consecutive starts.

The Mariners prevailed over the Astros on Friday, breaking a tie atop the American League West. Seattle now holds a one-game lead with two more head-to-head matchups against the Astros to go. Whichever team wins this set will also take the season series -- that could be crucial since the head-to-head record serves as the first tiebreaker.