Seattle Mariners: Stock up, stock down

Here are a few Mariners that are trending up and down in 2023.

Stock up

George Kirby, pitcher:  After an outstanding rookie season in 2022, Kirby has followed that up with a strong first half in 2023. Making his first All-Star team, Kirby has solidified himself as one of the best pitchers in the American League at 25 years old.

7-7 on the season with a 3.21 ERA, Kirby is the MLB leader in BB/9 by a substantial amount with a 0.80. With only nine walks in 101 innings pitched, Kirby has demonstrated the elite control he has always possessed.

With the ability to control the zone and throw strikes, hitters don't have the chance to take a pitch off in an at-bat and it helps Kirby keep opponents off balance. The Mariners hope he can continue to help anchor the pitching staff for years to come.

Luis Castillo, pitcher:  Another member of the Mariners' talented rotation, Castillo has been everything as advertised since being acquired from the Cincinnati Reds in July of last season.

Starting 11 games after the trade in 2022, Castillo went 4-2 with a 3.17 ERA while striking out 77 batters in 65.1 innings in the regular season. He made two postseason starts going 1-1 with a 1.88 ERA over 14.1 innings.

Castillo has followed that up this season with a 5-6 record, including a 3.05 ERA and ranking just outside the top ten with 114 strikeouts. Making his first all-star team as a member of the Mariners, the one-two punch of Castillo and Kirby in addition to Logan Gilbert, Bryce Miller and Bryan Woo has helped form one of the best rotations in baseball.

Stock down

Kolten Wong, second base:  Acquired in the offseason, along with cash from the Milwaukee Brewers Wong is in the middle of the worst season of his 11-year career. 

He was brought in to provide his Gold Glove defense at second base while giving them a serviceable left-handed bat in the lineup. In 52 games so far, Wong is hitting .156 with five XBH and 13 RBIs in 154 at-bats.

After batting .262 and averaging 27 XBH with 37 RBIs over each of the past ten seasons, Wong will need to turn it around in the second half as he heads into free agency this offseason.

AJ Pollock, designated hitter: Pollock was signed as a free agent to add an experienced bat to the lineup and to help play a little left field when needed. Like Wong, this hasn't worked out so far in 2023.

After an average season with the Chicago White Sox in 2022, Pollock and the Mariners were hoping he would return to the form that saw him average a .282/.337/.519 slash line with 17 home runs and 50 RBIs in each of his three seasons as a member of the Los Angeles Dodgers from 2019-2021.

Instead, the career .276 hitter before the season has managed to hit only .167 with five home runs and 15 RBIs in 45 games on pace for the worst season of his 12-year career.