TUCSON, Ariz. -- Jessie Harper went 3-for-3 with three two-out RBI, helping third-ranked Arizona edge No. 23 Arizona State, 4-3 in the first game of this weekend's series at Hillenbrand Stadium.
 
Danielle O'Toole earned the victory to kick off her senior week to improve to 25-3 on the season. Once she settled in, the left-hander was dominant, retiring 13 of the final 15 batters she faced, not allowing a hit after the third inning. In all, O'Toole allowed three runs, two earned, on four hits with four strikeouts and three walks. Each of the four hits she allowed were singles; ASU had runners in scoring position in just three of the seven innings.
 
Arizona, meanwhile, struggled to solve ASU starter Breanna Macha (11-7), who allowed four runs, two earned, on six hits in the loss. Three clutch knocks from Harper were the difference.
 
The freshman went 3-for-3, her third career game with at least three hits and her seventh with at least three RBI. Harper stepped to the plate in the first, third and fifth. Every at-bat, Arizona was down to its final out of the inning, and every at-bat Harper came through.
 
The back-breaker came in the fifth after the bases were empty with two out. Mo Mercado drew a walk to extend the inning for Harper, who laced a double down the right field line to plate Mercado from first. It broke the 3-3 tie and was the eventual game-winner for the Wildcats, who improved to 46-4 on the season and 16-3 in Pac-12 play.
 
Arizona State fell to 27-15 with the loss, 6-10 in Pac-12 play. The victory was Arizona's 93rd all-time vs. ASU; the Cats are 93-51-1 vs. their in-state rivals.
 
Arizona scored two unearned runs in the bottom of the first inning, taking advantage of a pair of errors on the same play. Jessie Harper had an RBI in the frame.
 
ASU plated two runs in the second inning after an Arizona error and took the lead on a two-out RBI single in the third.
 
The Cats tied the game on Harper's second RBI of the game, a two-out single that scored pinch runner Eva Watson to tie the game. 
 
With the bases empty and two out in the bottom of the fifth, Mo Mercado drew a walk to extend the inning for Harper, who clubbed a double down the right field line to plate Mercado and give the Wildcats a 4-3 lead.
 
Up Next: Arizona and Arizona State meet on Saturday at 6 p.m. MST for game 2 of the series. The Cats are in search of their second straight series win over the Sun Devils and sixth series victory in seven tries in 2017.
 
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