NORMAN — Just one week after the Sooners’ shocked the college football world by defeating No. 1 Texas, they fell back to Earth.

Oklahoma lost 21-13 to No. 15 Kentucky on Saturday. The Wildcats outscored the Sooners 14-3 in the second half, and OU is now 3-3 overall and 1-2 in SEC play.

Here are the moments that defined the Sooners’ disastrous loss:

Kentucky had possession first. The Wildcats’ opening drive nearly stalled out, but quarterback Kenny Minchey found wide receiver Nic Anderson — a former Sooner — to move the chains near midfield.

Kentucky’s first drive was methodical. A few minutes after Anderson’s first down, the Wildcats faced a fourth-and-1 on the OU 23-yard line. Kentucky coach Will Stein, known for his aggressive play-calling style, elected to go for it. Running back Mikkel Skinner took an end-around to the right side and easily got past Adepoju Adebawore to give the Wildcats a first-and-goal.

Three plays after Skinner’s run, Minchey found a wide-open Willie Rodriguez for the game’s first points. Kentucky’s opening drive lasted 6:20 and took 13 plays.

Oklahoma responded with a methodical drive of its own. The Sooners were in danger of going three-and-out, but quarterback John Mateer hit Manny Choice for 18 yards and a first down.

The Sooners got to the Kentucky 40-yard line before Mateer took a 10-yard sack on first down. Mateer, though, responded with back-to-back quality throws. He connected with Jacob Jordan and Rocky Beers on plays of 10 and 11 yards, respectively, to keep the chains moving.

Like too many of OU’s drives this year, however, the opening possession eventually stalled. Jer’Michael Carter dropped a pass from Mateer on third down. The Sooners trotted out Tate Sandell, who connected on his 44-yard field-goal attempt.

After Kentucky’s long, easy first drive, the Wildcats couldn’t get in a rhythm on their second drive. Minchey ran for 15 yards on the first play before going backward one yard on the next three. Defensive end Jake Kreul and linebacker Kip Lewis combined for a sack on second down.

OU put together another strong drive after the stop and had a chance to cut into Kentucky’s lead. But on fourth-and-2 from Kentucky’s 10-yard line, the Sooners attempted a fake field goal. The Wildcats intercepted the off-balance throw from Jacob Ulrich and held onto their 7-3 lead with 8:22 left in the second quarter.

The Wildcats got past midfield on their ensuing drive, thanks to an 11-yard reception by DJ Miller. But an intentional grounding call and a couple of nice plays from OU’s defense ended the threat.

OU defensive end Danny Okoye was called for holding on the Sooners’ punt return, giving them horrible field position at the 10-yard line. But that didn’t stop the Sooners from going down the field and scoring before halftime. Oklahoma marched 90 yards down the field, and Mateer hit tight end Rocky Beers for a 20-yard touchdown pass to give the Sooners a 10-7 lead with 30 seconds left in the second quarter.

The Sooners and Wildcats traded punts to open the second half. Mateer used his legs to pick up a first down on OU’s opening drive, but a holding call moved the Sooners back. Kentucky logged one first down before it had to punt.

Isaiah Sategna has been Mateer’s most reliable target since he arrived on campus, and he helped the Sooners move down the field in the third quarter. Mateer connected with Sategna for 45 combined yards on two completions, moving OU deep into Kentucky territory.

Once again, though, the Sooners failed to score a touchdown. The Sooners rushed for six yards over two plays, setting up a third-and-4 from the eight-yard line. Mateer once again looked to Sategna, but his throw was off-target. Sandell made a 26-yard field-goal to extend OU’s lead to 13-7.

While OU’s lead was only six with 6:32 left in the third quarter, it looked like the defense was going to be able to keep the Sooners in front. In Kentucky’s first play after the field goal, defensive end Taylor Wein stuffed Wildcats tailback Jason Patterson for a loss of one.

The Wildcats got a first down after Wein’s tackle for loss. But the defense responded well again. On third-and-10, Kreul sacked Minchey for a 10-yard loss, forcing the Wildcats to punt.

Late in the third quarter, after the Wildcats’ punt, the Sooners had a chance to score again and essentially put the game out of reach for the visitors. OU moved the ball to the Kentucky 38-yard line, bordering on field-goal range for Sandell. But on a first down, Kentucky defensive lineman Mi’Quise Humphrey-Grace flew past E’Marion Harris and hit Mateer as he threw. Defensive back Ty Bryant was in coverage for an easy interception, which he returned 43 yards to the OU 44-yard line.

Even after the interception, OU held a six-point lead, and the Sooners nearly forced a three-and-out. But Patterson broke a couple tackles on third-and-5 to keep Kentucky’s drive alive.

A few plays after Patterson’s third-down run, Minchey found Rodriguez for his second touchdown of the game to give the Wildcats a 14-13 lead with 12:53 left in the game.

After a blown assignment led to Mateer’s interception, the offensive line struggled again on OU’s next drive. The Sooners went three-and-out, and Mateer was sacked twice on the short drive. Oklahoma gave the ball back with 10:53 remaining.

A short, 36-yard punt from Ulrich gave Kentucky good field position — and the Wildcats moved the ball quickly. Minchey completed back-to-back passes of 11 yards each before Anderson made a circus catch of 17 yards to get his team to the OU 12-yard line.

The Wildcats gained seven yards after Anderson’s catch, setting up a fourth-and-3 at the five-yard line. Kreul, the true freshman and former 5-star prospect, burst through Kentucky’s offensive line and slammed Minchey to the ground for a sack.

OU’s offensive line struggles continued after Kreul’s game-changing play. Mateer was pressured twice, and the Sooners gained only four yards before punting.

A holding call on first down prevented the Wildcats from putting together a methodical, game-ending drive. But Kentucky punter Wilson Berry did his job after the three-and-out, pinning the Sooners at their own four-yard line with 2:35 to play.

The Sooners got two first downs after starting their drive at the four. But on the sixth play of the possession, Mateer threw an interception into the hands of defensive back Jordan Castell, who returned it 41 yards for a touchdown. The pick-six gave Kentucky a 21-13 lead with 1:17 remaining.

Trailing by eight, the Sooners got one last. Mateer found Choice down the field for 23 yards to get to OU’s 46-yard line with 34 seconds left. But two plays later, Mateer threw his third interception. Kentucky took a knee and sealed its 21-13 win over the Sooners.