Kade Anderson lowers ERA to 1.02 at Double-A

Woo completed six innings in the win tonight, but he was only at 75 pitches, and it sounds like he would have continued if not for the shoulder issue getting him lifted as a precaution. Woo said after the game that he wasn’t concerned about it. Still, if he winds up on the IL, that would open up a spot for top prospect Kade Anderson. Anderson, though, should really be in the majors regardless.

The time to stash Anderson was weeks, if not months, ago. Now, his arrival in Seattle appears imminent, especially after the Mariners jettisoned veteran Luis Castillo at the trade deadline earlier this week. The 22-year-old pitching phenom, who was selected third overall in last year’s draft, has authored one of the most dominant professional debuts in recent memory, posting a microscopic 1.13 ERA and 0.65 WHIP with a staggering 128/12 K/BB ratio across 87 2/3 innings. Seattle can promote Anderson later next week while preserving his rookie eligibility for next season. Mariners president Jerry Dipoto told reporters earlier this week that he will work as a traditional starter, and won’t pitch in relief, when he jumps to the big leagues. At this point, all signs point toward Anderson making his major-league debut next week. Simply put, he has nothing left to prove in the minors and represents a must-roster arm in all fantasy leagues.

Seattle didn’t move on from George Kirby or Emerson Hancock at the trade deadline, but they managed to ship veteran Luis Castillo to the White Sox over the weekend, which could open up a rotation spot for Anderson. The 22-year-old top pitching prospect figures to arrive at some point in mid-August so that he’ll remain rookie-eligible for next season. He’s put together a sublime professional debut with a microscopic 1.20 ERA and 119/12 K/BB ratio across 82 1/3 innings over 16 starts for Double-A Arkansas. Needless to say, Anderson should’ve been stashed in most fantasy leagues a while ago.

Passan adds that the sense is that Kirby is available and could be moved prior to Monday’s deadline. He also notes that Seattle has been listening to offer for Emerson Hancock and Luis Castillo. The Mariners have top prospect Kade Anderson knocking on the door of the majors and figure to move at least one, if not more, of their current rotation members. Kirby would net the largest return in any potential trade package, despite holding a pedestrian 3.98 ERA across 120 innings this season.

It’s fair to wonder whether Seattle will wait until mid-August to promote Anderson since that would allow him to remain rookie-eligible for next season. There will be a rotation spot open one they move on from either Emerson Hancock or Luis Castillo ahead of next week’s trade deadline. There’s a chance that both of them are on the move. Anderson has checked every metaphorical box during his professional debut with a microscopic 1.20 ERA and 119/12 K/BB ratio across 82 1/3 innings over 16 starts for Double-A Arkansas. Needless to say, Anderson should be stashed in all fantasy formats. His time is coming.

Anderson drew the starting assignment for the American League and delivered a near-flawless 10-pitch frame that perfectly encapsulated the polish that has made him one of the top pitching prospects in baseball. He coaxed a pop up from Eli Willits and got Roldy Brito to ground out before surrendering an opposite-field single to Jesús Made. He managed to get out of the frame unscathed by inducing a deep fly ball from Charlie Condon. He averaged 94.3 mph on his four-seam fastball and topped out at 95.4 mph. The 22-year-old southpaw has authored a dominant professional debut, compiling a pristine 1.36 ERA, 0.69 WHIP and 108/10 K/BB ratio across 72 2/3 innings over 14 starts at Double-A Arkansas. He’s on track to reach Seattle later this summer and offers enough strikeout upside to make an immediate fantasy impact upon arrival.

Anderson has put up video game-like numbers in his professional debut this season, compiling a sparkling 1.36 ERA and 108/10 K/BB ratio across 72 2/3 innings over 14 starts. All of the damage against him on Friday came on a pair of solo homers. The 21-year-old southpaw is at the forefront of any best pitching prospect in baseball debates and will headline the American League’s roster at the All-Star Futures Game in a couple weeks. He’s a strong candidate to skip Triple-A entirely and join Seattle’s pitching mix later this summer, either as a traditional starter or a multi-inning relief weapon.

Anderson along with organization mate Ryan Sloan are both top ten prospects in all of baseball, according to MLB Pipeline, ranking fifth and eighth, respectively. They are the only teammates on the American League team both ranked inside the top 25 overall. They will be joined by Athletics SS Leo De Vries (MLB Pipeline’s number two prospect), Red Sox SS Franklin Arias (seventh-overall prospect), Rays outfielder Theo Gillen (ninth-ranked prospect), and many more. The 2026 Future Game will take place Sunday, July 12 at Noon ET on NBC.

Anderson’s remarkable 27 1/3 scoreless innings streak was snapped in the opening frame on Friday night, but he still managed to turn in another dominant performance. He’s recorded at least eight strikeouts in eight of his first 13 professional starts since being selected third overall in last year’s MLB Draft. He’s put together one of the best Double-A campaigns in recent memory with a microscopic 1.22 ERA, 0.71 WHIP and 99/10 K/BB ratio across 66 2/3 innings. The 21-year-old southpaw has emerged as the top pitching prospect in baseball and should arrive in Seattle at some point later this summer following next month’s All-Star break. He’s a viable stash candidate in all fantasy formats based on his massive strikeout upside.

There’s a lot to unpack here. According to Mariners general manager Justin Hollander, it was a unanimous decision by all six starters — Logan Gilbert, George Kirby, Bryan Woo, Emerson Hancock, Bryce Miller and Luis Castillo — to move to a schedule where each pitcher will rotate through and have piggyback days. Ironically, the arrangement will begin with Castillo piggybacking out of the bullpen with Miller during Friday’s series opener against the Red Sox. The decision will have a significant fantasy impact simply by reducing the overall volume for each starter over the next few weeks. The unorthodox arrangement feels like a temporary stopgap solution until the arrival of top prospects Kade Anderson and Ryan Sloan later this summer ultimately forces Seattle to move on from at least one of their veteran arms.