SAN ANTONIO, Texas - Christina Rodriguez' double to the left-field gap plated the game-winning run to give St. Mary's a walk off 4-3 win over Midwestern State in the finale of the STMU NCAA Division II Classic Sunday morning at the SAISD Spring Sports Complex.

The Rattlers' game winning rally in the bottom of the seventh inning foiled a three-run comeback by the Mustangs, who fell to 3-2 on the season.

Midwestern State plays host to Abilene Christian in its home opener in a Tuesday afternoon doubleheader at Mustangs Park. First pitch is set for 1 p.m.

The Rattlers (4-0) touched up MSU starter Katie Petersen with three runs in the second inning as Rodriguez led off the inning with a double to the same left-field gap she would find in the seventh inning before Chelsea Wenske drove her with a single which preceded another single by Alyssa Alfarro.

Petersen, who struggled with her command early in the contest, issued consecutive walks to allow St. Mary's the second run of the inning before Lauren Miller pushed a sacrifice fly to center field to score Alfaro to give St. Mary's a 3-0 advantage.

Petersen settled down to allow two hits over the next four innings to keep the Mustangs within striking distance.

Midwestern finally came alive against St. Mary's starter Arlynda Flores in the sixth inning.

Nicki Duff and Natalie Rodriguez one-out singles before Courtney Bingham reached on an error to load the bases.

Mallory Mooney drove in a run with a single to left field before Carey Campbell reached on a fielder's choice to plate a second run.

Bingham would then come around to knot the game at 3-3 on Lauren Craig's single through the right side of the infield off of STMU reliever Heather Haas, who came in relief of Flores earlier in the inning.

The Mustangs threatened in the top of the seventh as McKenzie Sickler led off with a single and appeared to be safe on a stolen base attempt, but rolled off the base after the ball hit her in the ribs and was promptly tagged out.

Elena Bennett followed with an infield single, but Haas got Duff to roll out to first and Rodriguez to bounce back to the pitcher to end the threat.

Petersen, who fell to 1-2 on the season, sent the first St. Mary's batters in the seventh down in order before Kelly Baker drew a walk then advanced to second on a Flores single and scored on Rodriguez second double of the contest.