College baseball's opening weekend delivered thrilling action with upsets and historic performances. UCLA retained the No. 1 ranking despite a loss to UC San Diego, while Baylor's Tyce Armstrong made history with three grand slams in a single game. LSU and Texas both started 3-0, joining the Bruins in the upper tier of the rankings.

Louisville's series loss to Michigan State caused the biggest shakeup, dropping from No. 8 to No. 15. Vanderbilt and Arizona fell out of the rankings entirely, replaced by Oklahoma and West Virginia. The Sooners' 3-0 start included a win over TCU, while the Mountaineers swept their opening series.

This week's marquee matchup features No. 7 TCU visiting No. 1 UCLA in a top-10 showdown. The Horned Frogs, riding momentum from wins over Vanderbilt and Arkansas, face a tall task against the Bruins and star shortstop Roch Cholowsky. With LSU's Jake Brown hitting a grand slam in a 21-7 win and Oregon State's dramatic walk-off victory over Stanford, the season is already shaping up to be one of the most competitive in recent memory.