The Buffs didn't expect it to end like it did, though.

On Friday night, host Denver scored twice in the first 5 minutes and rolled to a 4-1 win over the Buffs in the Denver Invitational at Ciber Field.

"We're a work in progress," first-year CU head coach Danny Sanchez said. "We knew we were going to lose at some point. We're disappointed it was DU and, really, we got worked tonight."

CU (3-1-2) had never been unbeaten through its first five games of a season and the Buffs had allowed just three goals all season coming in.

Denver didn't take long to match that goal total. The Pioneers (4-1-1) had three goals in the first 23 minutes.

Sam Harder sent a direct kick from 28 yards out over the head CU goalkeeper Annie Brunner and into the net just 2:42 into the game. Just 2:05 later, Nicholette DiGiacomo took a pass from Kristen Hamilton and, from 25 yards out, sent a low shot towards the goal that got under a diving Brunner.

"You've got to give DU a lot of credit," CU senior Amy Barczuk said. "They came out and they put two away really quickly and that's always really hard to come back."

In CU's previous game, on Sunday at Northwestern, the Buffs fell behind 2-0 in the first 15 minutes, but rallied for a 2-2 tie.

The difference this time?

"DU's better," Sanchez said. "The big picture was that Denver has a more quality attack and kept shoving it down our throat."

Denver didn't let up, narrowly missing another goal when Hamilton had a shot that sailed barely over the crossbar.

Hamilton made it 3-0 in the 23rd minute when she scored from top of the goal box.

From there, CU did all it could to stop the bleeding.

Brunner made a pair of nicesaves and defender Lizzy Herzl made a great play on Hamilton to keep the Pioneers from adding to their lead.

"It was 3-0 at halftime, and we were hanging on by a thread for it to be 3-0," Sanchez said. "We didn't play great, but all the credit to Denver. They were all over us early."

CU played better in the second half as it tried to claw back into the game.

In the 60th minute, the Buffs worked the ball to the front of the net. Anne Stuller headed it toward the net and a DU defender deflected it in for an own goal.

CU kept the pressure on, but had another defensive breakdown in the 69th minute. In trying to clear the ball, the Buffs booted it right to DU's Anna Willis, who punched it past Brunner for a 4-1 Pioneers lead.

The Pioneers hung on from there to beat the Buffs for the third straight year and for the fourth time in the last five meetings.

"It was really frustrating and things weren't exactly clicking for us," Barczuk said. "That sometimes happens and it's unfortunate it was this game, but you have to give DU a lot of credit. They played extremely well."

Earlier on Friday, UC Irvine defeated Cincinnati, 2-1.

The Denver Invitational continues on Sunday with CU playing Cincinnati at 11 a.m., followed by DU vs. UC Irvine.

Against Cincinnati, the Buffs are hoping to get back on track and get their momentum back.

"We were going to get that loss eventually," Barczuk said. "We can take a lot of things form this game and learn from them. We have three more non-conference games before the Pac-12 and we have a good opportunity to finish strong. We need to put this game into perspective and finish strong the rest of our non-conference games."

Notable

CU leads the all-time series 8-7-1. ... DU had not allowed a goal in 343 minutes before the own goal. ... True freshmen Heather Ward and Taylor Thurmond made their collegiate debuts for CU. ... Brunner had played every minute of the season in goal until Kayla Millar entered the game in the 74th minute. ... Friday's loss matches CU's worst-ever defeat to an in-state rival. The Buffs had a 3-0 loss to Colorado College on Oct. 1, 1997. ... DU's four goals are the most CU has ever allowed to an in-state opponent. ... Friday was the 19th career loss for Brunner, one shy of CU's career record (20 by Sloane Cox from 1997-98). Brunner also ranks in CU's top four for wins, ties and shutouts. ... ... Between the two teams, there are four Fairview High graduates (CU's Anne Stuller and Nikki Machalek and DU's Caitlin Higgins and Cassidy Larson) and Boulder High graduate Katy Van Lieshout (Denver).

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Denver 4, Colorado 1

At Ciber Field, Denver

Colorado (3-1-2) 0 1 -- 1

Denver (4-1-1) 3 1 -- 4

Goals (assists) -- DU: Sam Harder, 2:42; DU: Nicholette DiGiacomo (Kristen Hamilton), 4:47; DU: Kristen Hamilton (Kalie Vaughn), 22:39; CU: own goal, 59:19; DU: Anna Willis (Kaitlin Bast), 68:59.

Goalkeepers (Min-Goals allowed-Saves) -- CU: Annie Brunner (73:58-4-3), Kayla Millar (16:02-0-1; DU: Lara Campbell (77:05-1-5), Maria Khan (12:55-0-1).