Mariners ALDS roster stands to get even thinner after ace Bryan Woo is left off

The Seattle Mariners submitted their roster for the American League Division Series opposite the Detroit Tigers on Saturday, and the absence of Bryan Woo's name is the big story. It's disappointing, albeit not totally unexpected.

Though the Mariners struck an optimistic tone on Woo's availability for the ALDS — for which Game 1 is set for Saturday at 5:38 p.m. PT at T-Mobile Park — in the days after he left his start on September 19 with tightness in his right pec, the situation seemed to take a dark turn on Thursday. Woo was able to throw a bullpen session, but said he wanted to see how he felt in a week's time.

The writing was on the wall at that point, and now it's right there on paper. The Mariners' ALDS roster does not feature Woo, though it does feature surprises such as the inclusion of Ben Williamson and Harry Ford, who have combined for eight plate appearances in the majors since July 31.

Not having Woo to throw at the Tigers is undeniably a huge blow to the Mariners. He was their best and most consistent pitcher during the regular season by way of a 2.94 ERA over 186.2 innings, and he was by far their most effective starter on the road with a 3.40 ERA. He would have been a perfect choice to start Game 3 in Detroit on Tuesday.

Sans Woo, the Mariners have chosen to take a risky approach with George Kirby in Game 1 against Troy Melton and Luis Castillo in Game 2 against reigning AL Cy Young Award winner Tarik Skubal. Logan Gilbert is lined up for Game 3, which would limit him to just one start in the series.

Josh Naylor's paternity leave will make the Mariners' ALDS roster even thinner

Meanwhile, here's a look at the Mariners' starting lineup for Game 1:

This is the standard starting nine that Dan Wilson was using toward the end of the regular season, and why not? Everything clicked for the offense in September, as it led the majors in runs, home runs and wRC+ for the month.

Here's the catch, though: Naylor may not be able to stick around for long.

As noted by Daniel Kramer of MLB.com, Naylor and his wife are expecting their first child any day now, which means there's a possibility of the All-Star first baseman going on paternity leave before the ALDS is over. He will be allowed to miss up to three days.

The Mariners will be able to replace Naylor on the roster if he does go on leave, though their current 26-man mix makes it seem as if they're already prepared to pivot. With Williamson available to play third base, the door is open to shift Eugenio Suárez to first base if the Mariners would rather keep Luke Raley on the bench.

Though Suárez has been putting in work with Perry Hill at first base, he has never started a game at the cold corner in his career. In the four innings he played there after rejoining the Mariners on July 30, he made one error.

The Mariners' perfect-world scenario involves having Naylor at first base for the entire ALDS, not to mention the rest of the postseason if they advance. He was one of their best hitters down the stretch to the tune of a 137 wRC+, and he had arguably the biggest hit of their season. Yet nobody will be in a position to complain once he goes on paternity leave. It will be "next man up" and go from there.

The Mariners are still favored to win the series, and we remain of the mind that the Tigers are a more favorable matchup than the Cleveland Guardians would have been if they had beaten Detroit in the AL Wild Card Series. And if the Mariners do survive the series, that will hopefully be the last time they have to win games this October without Woo or Naylor.