"We took a great time like Fort Smith, we grinded and found a way to win," MSU assistant coach Tres Segler said. "X (Blackburn) is capable of so much basketball. He has grown up so much with his game this year."
Midwestern gets a rematch with rival and No. 3-ranked Tarleton State in the semifinal round Sunday night at 6 p.m. (Central Time).
The Mustangs broke open a close game by closing the opening half on a 10-2 run highlighted with seven points by Blackburn, who canned his trey of the game to give the Mustangs a 41-36 edge at the break.
Blackburn hit 5-of-9 shots scoring 17 of his points and grabbing seven rebounds before halftime.
MSU continued the run by outscoring the Lions 9-3 in the opening three minutes of the second half to push the advantage to 50-39 on an Eddie D'Haiti triple at the 17:01 mark.
"We made some good rotations which allowed us to string together some stops early in the second half," Segler said.
The Mustangs limited UA-Fort Smith to a season-low output of 66 points on 34.4-percent shooting, but struggled from the floor to a 31.4-percent clip hitting just 24.2 percent in the second half allowing the Lions to chip away at the lead.
Seth Youngblood and Alex Cooper combined for 13 points each while Jake Toupal and Blake Branham added 12 and 11 points, respectively, to spur the UAFS comeback effort.
The Lions crept back to within a basket on two occasions and were within 68-66 of MSU when Alex Cooper hit a runner with 16 seconds remaining.
But the Mustangs sealed the victory by going 6-for-6 from the charity stripe in the game's final minute with two each from Blackburn, Monzaigo Williams and JaMichael Rivers.
Rivers was the only other Mustang in double figures with 14 points on 5-of-12 shooting including a pair of 3-pointers in 23 minutes off of the bench, while Williams delivered a solid all-around performance with eight points, 12 rebounds and six assists.
"Z (Williams) just seems to find what we need in a game and just do it," Segler said. "He had a great active game and seemed to get to all the balls that were loose. We'll probably look back at film and that will be what won us the game."
Senior forward Eddie D'Haiti chipped in nine points and snared five rebounds, while senior guard DeJuan Plummer had seven points and three assists off of the bench.
Midwestern improved to 7-0 in South Central Region first-round games, while UA-Fort Smith lost in its first NCAA Division II postseason appearance.
The Mustangs moved to 23-7 on the season, while the Lions close the campaign at 21-7.
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