(Over the next week, we will be examining each of the A's arbitration-eligible players to determine whether they will return in 2019.)
Sean Manaea was having the best season of his career before undergoing season-ending shoulder surgery, which is expected to keep him out for most, if not all, of 2019 as well.
Manaea, 26, went 12-9 with a 3.59 ERA and 1.08 WHIP in 27 starts, striking out 108 and walking 32. The left-hander was the ace of the A's staff for most of the season, and he threw his first career no-hitter on April 21 against the league-leading Boston Red Sox.
Manaea earned just $550K in his third Major League season, but he is projected to get a raise to $3.8 million in arbitration, according to MLB Trade Rumors.
Why he might be a bargain
Even though Manaea is expected to miss the vast majority of the 2019 season, it's a no-brainer for the A's to keep him. At 26 years old, he has plenty of good years in front of him, and he proved he can be a top of the rotation type pitcher.
Manaea has said his shoulder bothered him for the entire season, and yet he was still able to post excellent numbers and throw a no-hitter. His velocity was down for much of the season, likely due to his shoulder injury, but he learned how to utilize his secondary pitches and became a better all-around pitcher in the process. If he can get back to full healthy, he should be a number one or two starter on the A's for years to come.
Why he might be too pricey
The only way the A's would let Manaea go is if they believe he will not recover from the shoulder surgery. Spending $3.8 million on an injured pitcher obviously involves some risk, but based on all reports, his surgery went as well as they could have hoped.
Assuming Manaea's prognosis is good, he should remain in Oakland, not just in 2019, but for years to come. The left-hander has already developed into a top flight pitcher in the American League, and at the age of 26, he hasn't even hit his prime yet.
Manaea also fits in well in the A's clubhouse and feels very comfortable pitching in Oakland. He has a great relationship with the fans and in the community, and he can be a face of the franchise for several seasons.