The Mariners placed Woo (elbow) on the 15-day injured list Thursday.

EDGE Analysis

Woo was on track to be included in the Mariners' Opening Day rotation until he was unable to get loose during a bullpen session earlier this week. According to MLB.com, Woo underwent an MRI that revealed "mild inflammation" and no structural damage. Though he seems to have avoided a major setback, Woo will still be shut down from throwing until early next week and will require some time to build back up. Emerson Hancock was recalled from Triple-A Tacoma on Thursday and will fill a back-end spot in the Seattle rotation until Woo is ready to come off the IL.

Woo will be placed on the 15-day injured list due to elbow inflammation, Ryan Divish of The Seattle Times reports.

EDGE Analysis

Divish notes that Woo felt discomfort while warming up for his last side session, and he ultimately couldn't get loose. He later underwent an MRI, which came back clean. The Mariners are hopeful that Woo can let the inflammation calm down over the next 7-to-10 days, at which point he can resume throwing. Emerson Hancock will take Woo's place in the starting rotation to begin the season.

Woo fired four perfect innings during which he recorded five strikeouts in a Cactus League win over the Brewers on Thursday.

EDGE Analysis

Woo has bounced back from a forgettable Cactus League debut against the Rockies on March 1 to throw 6.2 hitless innings over his next two appearances. Daniel Kramer of MLB.com reports the right-hander needed just 38 pitches to record his 12 outs Thursday, necessitating another dozen pitches in a bullpen session after his appearance in order to continue building up for the start of the season. The Mariners will monitor Woo's workload throughout the season as they prepare to push him well past the 131.2 innings he threw in 2023 as a rookie.

Woo was credited with the win in Thursday's Cactus League victory over the Angels, firing 2.2 scoreless innings during which he allowed a walk and recorded three strikeouts.

EDGE Analysis

It was a key outing for Woo despite the fact it came early in spring, considering he'd been roughed up for four earned runs on six hits over 1.2 innings by the Rockies in his Cactus League debut last Friday. Steve Stockmar of MLB.com reports Woo needed just nine pitches to get through the first inning and threw 22 of his 38 pitches for strikes. While the Angels lineup was missing several key regulars, including Mike Trout, both Woo and manager Scott Servais came away pleased with the progress the right-hander displayed during his start. "He came out with a plan today and executed," Servais said. "He wanted to get both of his fastballs going and he did just that. He threw the ball really well. Great to see, super aggressive, had tons of strikes, and had really good stuff on top of it."

Woo, who logged 18 starts as a rookie in 2023, is focusing on improving considerably against left-handed hitters in his second season, Brandon Gustafson of 710 ESPN Seattle reports.

EDGE Analysis

The right-hander, who made the jump straight from the Double-A level to the majors, finished with a 4-5 record and serviceable 4.21 ERA and 1.21 WHIP across his first 87.2 big-league frames. However, Woo had some drastic splits, surrendering a .283 average and .928 OPS to the 180 left-handed hitters he's faced, numbers exponentially worse than the respective .179 and .494 figures he surrendered to righty bats. Woo, who's penciled in as the Mariners' No. 5 starter as spring camp gets underway, says he is absorbing plenty from two other accomplished young arms above him in the rotation in George Kirby and Logan Gilbert, who already have solid major-league resumes. "To have guys like that that have already have so much success, but also be so young and they're not that far removed from kind of where you are, where I am now, it helps a lot," he said.

Woo allowed two hits and three walks while striking out five over 3.2 shutout innings in a no-decision versus the Rangers on Friday.

EDGE Analysis

While he didn't give up a run, Woo needed 82 pitches (44 strikes) to get 11 outs. Manager Scott Servais elected not to push the young right-hander further, and the bullpen was able to keep the shutout going with 5.1 scoreless innings distributed between five relievers. Woo finishes the regular season with a 4.21 ERA, 1.21 WHIP and 93:31 K:BB as well as a 4-5 record through 18 starts spanning 87.2 innings. He also logged 44 innings with a 2.05 ERA with Double-A Arkansas after throwing just 57 innings across three levels last year. Should the Mariners push their way into the postseason, Woo would likely work out of the bullpen if he gets onto the playoff roster at all.

Woo (4-5) allowed six runs on five hits and two walks while striking out six in just 3.1 innings during a loss to the Rangers on Sunday.

EDGE Analysis

Sunday was a nightmare outing for Woo, who had given up just six home runs in 16 starts heading into the day but surrendered four long balls and recorded just 10 outs in Texas. Marcus Semien led things off with a solo blast in the first followed by a two-run shot from Corey Seager in the third. Adolis Garcia then kicked off the fourth with a homer and Woo was finally pulled after Leody Taveras went deep just three batters later. Woo has sandwiched two scoreless outings in between two poor outings during which he combined to give up 11 runs. He'll look to end the regular season on the right foot with a rematch against the Rangers this weekend.

Woo (4-4) allowed three hits and four walks while striking out six over five shutout innings to earn the win Monday over the Athletics.

EDGE Analysis

While Woo's four walks were a season high, he was able to turn in his third scoreless outing in his last four starts. Two of those efforts have been against Oakland, so there is somewhat of a caveat for the quality of the opponent, but it's still encouraging to see the rookie find a groove late in the year. Woo is at a 3.90 ERA, 1.17 WHIP and 82:26 K:BB through 80.2 innings over 16 starts. He is projected to make his next start on the road versus the Rangers this weekend.

Woo (3-4) allowed four hits and struck out eight without walking a batter over 5.2 shutout innings to earn the win Tuesday over the Angels.

EDGE Analysis

Woo received some extra rest between starts, and it seems that paid off for the Mariners. He threw 67 of 83 pitches for strikes, and just one of the four hits he allowed went for extra bases. The rookie right-hander has won two of his last three outings, allowing five runs over 16.2 innings in that span. He's at a 4.16 ERA, 1.15 WHIP and 76:22 K:BB through 75.2 innings through 15 starts. Woo's tentatively projected for a favorable road start in Oakland next week, though it's unclear if the Mariners will build in any additional time off for him as they remain in pursuit of a playoff spot.

Woo will start Tuesday against the Angels, Daniel Kramer of MLB.com reports.

EDGE Analysis

Woo had his previous turn in the rotation skipped, though he'll be called on just four days later, so it's perhaps more accurate to say that he'll merely be receiving a few extra days of rest. Woo has had his moments this season, but his ERA now sits at 4.50 after he allowed five runs in five innings against the Reds in his most recent start. Given that his 114 innings between the majors and minors this season far outpace the 57 he threw last season, it's reasonable to expect him to be handled very cautiously down the stretch.