20-year-old Lin Wei-en was promoted to Triple-A by the Athletics, becoming the youngest pitcher in the Pacific Coast League.

Overseas lefty Wei-En Lin was recently seen in the Athletics' Triple-A bullpen area, and today the team formally announced his move to Triple-A. At age 20, he is set to be the PCL's youngest pitcher this season.

Lin, who jumped three levels in his first professional season last year—starting at Single-A and ending at Double-A—has made 10 starts in Double-A this season, tossing 51.1 innings with 53 strikeouts and 13 walks, posting an excellent 1.93 ERA. Opposing hitters managed a weighted on-base average (wOBA) of just 0.221 against him, ranking in the 100th percentile, proving he needs a higher level of competition. Now the Athletics have decided to promote him to Triple-A.

MLB.com recently ranked Lin among its midseason Top 100 prospects at No. 91, noting that all his pitches have at least Major League average potential, with his curveball and slider receiving the highest grades. His greatest strength is his command of all pitches, making him a potential back-of-the-rotation starter.

After moving to Triple-A, Lin will not only face older, more experienced hitters (average age 27.2), but also the challenge of pitching in the hitter-friendly Pacific Coast League. The PCL has long been known for favoring batters; this season, teams average 5.88 runs per game, and pitchers have a collective 5.48 ERA. According to Baseball America, the Athletics' Triple-A home park has a run-scoring park factor of 126 and a home-run factor of 139, both the most hitter-friendly in the entire PCL.

Currently, besides Chen-Ao Chuang, who will share the same team as Lin, another pitcher is also active in the Pacific Coast League: Yu-Min Lin of the Arizona Diamondbacks. Yu-Min Lin has made 11 starts this season covering 44 innings, with 7.0 strikeouts per nine innings and 5.7 walks per nine, posting a 5.11 ERA that is still below the league average. Chen-Ao Chuang has 6 appearances totaling 25.1 innings, with 6.4 strikeouts per nine and 3.9 walks per nine, and a 7.11 ERA.