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Arias is an extremely advanced hitter already, playing all of 2025 at age 19, so much so that the Red Sox challenged him by moving him up from Low A after just 19 games there in April (and only 54 games there in total). He responded with one of the highest contact rates of any hitter in High A, regardless of age, striking out just 8.9 percent of the time, second among qualifiers behind a 24-year-old org player, while flashing some of his power potential and playing strong defense at short. He rarely swings and misses, with an overall whiff rate of just 12 percent on the year, and just 4 percent on pitches in the zone. He might benefit by swinging a little bit less often — at least until he gets stronger and can do more with the contact he is making, as right now he’s getting the bat to the ball but doesn’t square it up consistently enough, with a weird spike in his pop-up rate in High A last year. He’s barely begun to fill out physically, with room to add probably a full grade of power as he matures, but he’s such a smart hitter that he’s moved up the chain faster than most prospects his age. He’s a natural shortstop with excellent instincts and is at least a 55 defender there already, probably plus or better in the end. He’s less of a finished product than the other players around him in this range of the list, but if he were a college sophomore right now, we’d be talking about him as a potential 1-1 pick in 2027.