But for the second time in the tournament, senior midfielder Tatyanny Griffiths provided the difference as the Mustangs claimed its fourth LSC postseason title surviving 4-2 in penalty kicks.
Midwestern earns the automatic bid into the NCAA Division II South Central Regional for the third time in school history -- all in the last four seasons -- as the Mustangs advanced to postseason play in 2010 and 2011.
The playoff field will be announced Monday night at 6 p.m. via a Web stream on NCAA.com.
"This is a group that has the ability to stay even keeled," MSU coach Jeff Trimble said. "We needed that because we created a lot of chances that we just didn't finish. When you do that, you're really setting yourself up to fail."
Cottrell, the league's reigning offensive player of the year, broke open a scoreless match with her ninth goal of the season in the 49th minute off of a great serve from senior midfielder Mickey Brown.
"Mickey did a great job of working to the end line and putting the back on goal with a soft serve to the center," Trimble said.
Cottrell was able to corral the ball and knock it into the empty net.
West Texas A&M which was going for its fourth straight victory after winless October didn't back down.
"They really stepped it up in the second half especially after we scored," Trimble said. "We went through periods of time where we lost the midfield and that caused us some problems."
WT junior midfielder Jessie Thomas got behind the Mustangs' defense with the equalizer in the 63rd minute then took advantage of chaos on the box for her second score in the 87th minute off of a serve to the middle of the box to give the Lady Buffs a 2-1 advantage just minutes away from clinching a postseason berth.
"We didn't defend it very well and we left people open. We were scrambling and got very disorganized," Trimble said.
The Mustangs didn't panic as less than 90 seconds later the same combination worked again.
Brown charged down the right wing, hit a great ball to a charging Cottrell who one-timed it for her 10th goal of the season to send match to overtime.
"Everyone went nuts," Trimble said. "We were getting to the end line and at times we weren't running into the box to get a good finish. It was a very nice goal."
The teams exchanged three shots each during the two overtime periods resulting in the Mustangs second shootout of the weekend. MSU had advanced past Texas A&M-Commerce 3-1 on PKs after battling to a scoreless draw Friday afternoon.
"This seems to be our thing," Trimble said. "I was a little worried about using the same lineup, but they were really calm. I didn't want anyone taking a PK that if they weren't comfortable taking it. My assistants (Amanda Snodgrass and Kyle Redding) did a really good job of organizing the girls and it worked."
The teams exchanged makes in the opening two rounds before Thomas missed off of the left post and Haley Girard went wide right to spell doom for the Lady Buffs. Cottrell, Morgan Hannon, Katie Huff and Griffiths converted PKs in succession for the Mustangs, who successfully converted seven of eight times from the penalty mark in tournament play.
Joining Cottrell on the all-tournament team was Brown, senior goalkeeper Kallie Essary, senior defender Anna Molen and senior forward Emily Saville.
Midwestern State moved to 13-4-3 on the season while West Texas A&M went to 6-8-6.
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