During the 1999 season, the Athletics had a pair of highly touted left-handed pitching prospects. First-round pick Mark Mulder plied his trade at Triple-A while the following year’s first-rounder -- Barry Zito -- worked his way to Double-A. Fast-forward a year later and the two began to take the ball every fifth day alongside one another in a Major League rotation.
On the same night that MLB's No. 7 LHP prospect Gage Jump (ATH No. 3) earned his first Major League win at Wrigley Field, MLB's No. 6 LHP prospect turned in his best outing yet as a professional Tuesday night at Double-A. Jamie Arnold (ATH No. 2) spun seven scoreless frames in Midland’s 10-3 win over Northwest Arkansas at Arvest Ballpark.
Arnold buzzsawed through the Naturals’ lineup, giving up four hits and two walks while allowing more than four batters to come to the dish just once -- in his final frame. The 11th overall pick in the 2025 Draft consistently sat at the top rail of the strike zone with his fastball, collecting five strikeouts in total -- two on his heater, two on his slider and one on his changeup, a filthy lefty-on-lefty punchout of Carson Roccaforte (KC No. 16).
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MLB’s No. 28 prospect picked up the victory by virtue of a relentless RockHounds offensive attack in which all nine members of the starting lineup collected at least a hit. Leading the way was Leo De Vries (ATH No. 1/MLB No. 2), who posted his seventh three-hit game of the year while driving in a pair of runs and swiping a bag, his 17th of the season.
In an age in which clubs closely monitor the pitch counts of their prospects (especially the top ones), the Athletics have allowed Arnold to go full throttle as the calendar flipped to June. After tossing between 71 and 79 pitches in his first six starts, the former Florida State standout has thrown at least 93 in each of his past three outings, including a career-high 97 on Tuesday.
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Inherently, going deeper into games in the Texas League means more opportunities for the offense-friendly circuit to wear the numbers down. Arnold made five starts in May and allowed 40 hits over 25 1/3 innings, but only one left the ballpark. Just two qualified pitchers on the circuit -- including teammate Wei-En Lin (ATH No. 4) -- have posted an ERA below 3.50 thus far in 2026.
Entering the night, Arnold was running an unfathomably high .417 BABIP while garnering a 59 percent ground-ball rate, the second-highest in the Texas League. Those two stats together lay bare that he’s getting plenty of grounders but they’re finding holes at an unsustainable rate. Eventually, the clean frames will come, as they did Tuesday.
During Spring Training, Arnold was one of the buzziest names around Mesa, Arizona. He had yet to throw a professional pitch at that point, and since then, he's ascended nearly 50 spots on MLB Pipeline’s Top 100 Prospects list. Sure, a 4.53 ERA won't leap off the page but neither did Jump’s 4.50 ERA across nine starts for Triple-A Las Vegas. His last start before being promoted? Seven scoreless frames.
As the Athletics continue to jockey for positioning in the AL West and Wild Card races, they’ll keep tabs on an arm that has long tapped into his competitive nature. A top of the rotation with two promising phenom southpaws? A’s fans have been here before.