Another of Athletics’ 2016 first-round picks (in the Competitive Balance A (CBA) round at #37 overall – along with A.J. Puk (LHP, Athletics), at #6 overall) – Jefferies made his 2017 debut on April 9, starting for the High A Stockton Ports. Calf and shoulder injuries limited Jefferies to 50 innings in his junior season at Cal last year and knocked him into the CBA round, where the A’s were happy to pick him up. Oakland limited him to just 11 ⅓ innings of Rookie ball last season, and kept him off the mound during fall instructs, but he is healthy and pitching without restrictions to start the 2017 season.
Jefferies is part of an eight-man tandem rotation for the Ports, so he will be tapped at 65-pitches-per outing while pitching on three-days rest. He put those pitches to good use in his Ports’ debut, allowing just two first-inning singles in four frames. He retired the final 10 batters he faced and struck out two, while walking none and recording six ground ball outs.
Jefferies showed good rhythm and pace on the mound in his debut, and he mixed his pitches well. His two-seam fastball sat 88-to-92 mph and had late life down in the zone. Jefferies threw his cutter at 88-to-91 mph and it had sharp, late lateral bite. His slider averaged 79 mph and served as a change-of-pace, off-speed offering when played off of his two fastball offerings. Jefferies commanded his changeup well, and although it was coming in a bit firm in the 86 mph range, he was still able to get several hitters out on their front foot.
Jefferies isn’t a big guy by any means, but he generates a solid downhill angle from his clean, over-the-top delivery. An infielder in high school, Jefferies showed athleticism in his delivery and while defending his position. His repertoire and build are reminiscent of Tim Hudson (RHP, A’s, Braves, Giants, 1999-2015). Jefferies’ health will be closely monitored given last year’s injuries, but he is more polished at this point as a 22-year-old second-year pro, and he could reach Double-A Midland later this year. Early indications are that Jefferies has the stuff the A’s thought he’d have to justify the high draft choice. It’s not unreasonable to forecast a mid-rotation starter profile down the line for Jefferies, though it’s still a limited sample size of pro competition.