For the past two seasons, the Gophers have prided themselves on staying cool under any circumstances. After winning the first set of Friday’s NCAA regional semifinal, though, their famously steely mind-set wavered just a bit.

A crisp, efficient opening set against Missouri gave way to an error-filled followup at the Sports Pavilion, forcing the Gophers to reset their psyche after the Tigers evened the match 1-1. “I think the moment got big a little bit,’’ senior Sarah Wilhite said. “In between the second and third set, we did a really good job of just bringing it in, and taking advantage of the time we have in between points to kind of take a breath.’’

By the end of their 3-1 victory, the top-ranked Gophers were breathing easy again. They defeated No. 18 Missouri 25-15, 21-25, 25-19, 25-14 to earn a spot in Saturday’s regional final against UCLA, which beat North Carolina 3-1 in Friday’s second match.

Much of the Gophers’ composure and confidence comes from their balance, which was on full display Friday before a joyous crowd announced at 5,309. They got double-digit kills from five players, led by Wilhite’s 16, and four other players reached double digits in digs. Setter Samantha Seliger-Swenson logged 52 assists as she shared the bounty with all of her hitters.

Missouri staggered through the first set, hitting .073 before regaining its form in the second. But top hitter Melanie Crow had an off night, finishing the match with 12 kills and nine attack errors. The Tigers got 20 kills from senior Carly Kan but hit only .189 for the match.

The Gophers hit .351, including a sterling .667 in the fourth set.

“We had to weather the storm there for a while,’’ said Gophers coach Hugh McCutcheon, whose team won its 35th consecutive home match. “We hung in there. We made adjustments along the way, and we were able to get some points on the defensive end, which helped free us up.

“I’m very happy with the fact that we have a lot of people who can get it done. That’s been a trait of this group this year.’’

Before the match, Missouri coach Wayne Kreklow said the Tigers were in for “a huge challenge’’ against a Gophers team that extended its win streak to 13 matches. Like the Gophers, the SEC champions play a fast-paced style and rarely allow their emotions to run high.

They got off to a poor start Friday. The Tigers committed eight total errors in the first set, and an 8-1 run, which included four Tigers attack errors, put the Gophers ahead 9-4 in a set they led by as many as 10 points.

“[The Gophers] did an outstanding job of taking us out of what we want to try to do,’’ Kreklow said. “They served well enough that they kept us from getting into a rhythm. We weren’t hitting on enough cylinders for a long enough time.’’

While the Tigers settled down in the second set, the Gophers stumbled. They were hampered by 10 miscues, interrupting the flow they established early in the match. Missouri closed the set on a 6-2 run and evened the match, though Crow felt they still were not playing at peak form.

The Gophers roared back in the third after taking that deep breath. McCutcheon was particularly pleased with their serving and their discipline on defense. The Gophers never trailed in the third or fourth sets, powered by 10 kills from Hannah Tapp, nine from Wilhite and eight from Paige Tapp.

Saturday’s match will be the last at the Pavilion for six seniors, including Wilhite and the Tapp sisters. A victory would send them to the Final Four for the second year in a row and the fifth time in program history.

Hannah Tapp said she doesn’t expect any melancholy, only resolve.

“We’ve had a great run here,’’ she said. “We’re just going to try to do the best we can and give it our all.’’