BOULDER - Winning close basketball games usually starts with fundamentals, and a failure in one fundamental area ended No. 20 Colorado's chances Sunday afternoon against No. 7 California.

Failing to box out on Cal's late free throw attempts, CU watched its opportunity to split weekend games against a pair of Top Ten Pac-12 Conference opponents fizzle at the Coors Events Center.

It was Cal 53, CU 49 - and it was difficult to stomach for Buffaloes coach Linda Lappe.

"Boxing out was the difference in the game," said Lappe, whose team lost 57-40 two days earlier to No. 4 Stanford. "We were getting shoved under the rim; they were lower than us and quicker than us . . . they took us out of position and were athletic enough to go up and grab the rebound."

The Buffs were outrebounded 43-34, with the most critical lapse on the boards occurring in the game's final 15 seconds. Ahead by two and three points at the time, the Bears snared two offensive rebounds after missed free throws, maintaining possession each time and foiling the home team's bid for its first Pac-12 win.

After opening 11-0 and earning its highest national ranking since the 2003-04 season, CU dropped to 11-2 overall and 0-2 in conference play. Cal improved to 12-1, 2-0.  The Buffs play their third game in five days, returning to the Events Center on Tuesday at 6 p.m. to face Utah.

Chucky Jeffery (13) and Arielle Roberson (11) were the only two Buffs players in double figures. The Bears were led by Brittany Boyd's 15 points, with Reshanda Gray and Afure Jemerigbe adding 10 each.

With the exceptions of its breakdown in boxing out and encountering a pair of shooting droughts, much of what CU did was right. "But like coach said, we can't do everything well except something; we have to do everything well when we play a top-tier team in the country," Jeffery said. "We know the things that are going to get us beat."

What took the Buffs down Sunday began with 15.6 seconds to play and the Bears ahead 51-49. Cal guard Layshia Clarendon missed a pair of free throws, but Jeffery and Talia Caldwell battled for the second miss rebound and a tie ball was called.

With 13.2 seconds left, the possession arrow favored Cal. When the inbounds pass was made, Clarendon was fouled again - this time by Rachel Hargis - and this time she made one of two to give the Bears a 52-49 edge with 10.3 seconds to play.

Lappe called time out, drew up a play - but a shot was never taken. Jeffery turned it over on a drive to the basket and a back-side screen for a three-point attempt by Lexy Kresl never developed.

"Obviously we didn't get quite that far," Lappe said. "Even if we had, it wouldn't have been a great screen either . . . we were rushing a little bit too much."

Cal got possession on the turnover and CU's box out problem persisted.  Fouled with 4.5 seconds showing, Boyd missed both free throws but Afure Jemerigbe controlled the second rebound. With 2 seconds to play, she hit one of two free throws, giving the Bears a four-point lead and the win.

"We had more opportunities than we can ever expect," Jeffery said. "We have to bear down and box out . . . get a rebound. They gave us opportunities to rebound and we have to get tougher."

Lappe said the Buffs were "solid defensively for the second (game) in a row. Defense is a strong point for us, but you finish your defense with a defensive rebound."

The Buffs went through droughts in each half, scoring just three points during a 7:31 stretch in the first 20 minutes then suffering through an 11:46 span in the second half when they hit only two of 17 field goal attempts. CU finished at 35.2 percent from the field (19-for-54) and was held to under 50 points in consecutive home games for the first time since the 1974-75 season.

But the Buffs' defense kept them competitive. The Bears were held to 35.8 percent from the field (19-for-53), and Cal coach Lindsay Gottlieb left Boulder "proud of my team's grit . . . Colorado's an excellent team - a legitimate Top 20 team, very, very talented. We knew it was going to be a battle."

Defense, said Jeffery, "was the main reason we were in the game. There were a couple of stretches where we weren't scoring, but they weren't either . . . we were getting stops and that's what it takes."

Sunday's first half immediately took on a defensive flavor and that didn't change; the score was tied 24-24 at intermission. But for the Buffs, that was an improvement over their first-half production (14) against Stanford on Friday night.

On Sunday afternoon, neither CU nor Cal could manage more than a four-point advantage in the first 20 minutes. The Buffs got six consecutive points from Jeffery to start the second half. But as in the first half, creating any separation was a problem for both teams until Cal, whose only loss was at then-No. 4 Duke (77-63) on Dec. 2, increased its lead to five (43-38) on a baseline jumper by Eliza Pierre with 7:35 to play. And when Caldwell hit one of two free throws with 6:59 remaining, the Buffs faced a six-point deficit (44-38).

A short jumper in the lane by Clarendon put Cal up 46-38, and with 6 minutes left Lappe called a timeout as her team's offensive malaise continued. Reese finally snapped the dry spell with a turnaround jumper from the right baseline (46-40) and Roberson followed with her second trey of the game to cut Cal's lead to 46-43 at the 4:41 mark.

But one of two foul shots by Boyd and a put-back by Gray on Boyd's second miss sent the Bears back ahead by six (49-43), and one of two free throws by Clarendon made the Buffs' deficit seven (50-43).

Cal's eight-point lead (51-43) returned when Caldwell hit the first of two foul shots at the 2:53 mark - and time was slipping away for CU. A Jeffery basket with 1:59 left brought the Buffs to 51-45. Layups by Jeffery and Brittany Wilson pulled them to 51-49 with 16.7 remaining.

Next came the Buffs' fundamental flops in boxing out - and ultimately the loss.

"We need to learn how to push back against bigger and stronger post players," Roberson said. "I think that's what happened on the rebounds off the free throws . . . I think when it comes down to it, we have to put in a lot of effort and we have to find a way."

Contact: BG.Brooks@Colorado.EDU