Rondo, a 6-foot-1 sophomore, had 14 points, 5 steals, 5 assists and 0 turnovers, while making Hogs guard Ronnie Brewer earn his game-high 23 points.
"Time and time again, with the shot clock winding down, Rondo came up with a play," said UA coach Stan Heath. "That's what great players do."
Randolph Morris, Kentucky's 6-10 center, had season highs of 19 points and 8 rebounds to complement Rondo and six different Wildcats who made at least one 3-point shot.
The Wildcats (14-6, 4-2 in the Southeastern Conference) scored on 22 of their final 27 possessions to secure their fourth straight win, and sixth straight over Arkansas. They lead the series 20-7 overall and 9-2 in Lexington.
Smith said about Rondo, "For his size, pound for pound, he is as athletic a player as you get."
Arkansas (14-6, 3-4 SEC) started like a house afire, twice leading by 18 points (28-10 and 33-15). But it turned out that the Hogs were just borrowing the lead. They allowed 55 second-half points -- Kentucky's most in one half all season.
"We didn't play defense the same way in the second half as we did in the first half," Heath said. "And we didn't rebound as well. Kentucky hurt us with (13) offensive rebounds."
The Wildcats, after getting outrebounded 20-15 in the first half, pounded the glass for a 22-11 advantage in the second half and a 37-31 overall edge.
The tale of two halves left Kentucky coach Tubby Smith puzzled.
"At the beginning I didn't think much of our chances," Smith said. "Poor starts have been our profile all year, and I just don't get it. We were a little bit confused by Arkansas' 1-1-3 (zone) - that made us stand around. And their athleticism was intimidating us for awhile."
But Smith credited the Wildcats with a lot of grit, moxie and heart. He also cited the UK crowd.
"It was a chess game between the coaches, and a matter of will," Smith said. "We were trying to force them to play our tempo. We had a great crowd and that had something to do with it."
Kentucky went on a 19-4 run to transform a 57-51 deficit into a 70-61 lead, as Arkansas failed to make a field goal from the 8:20 mark to the 1:35 mark. The Hogs made just four free throws in that stretch.
Wildcats senior guard Patrick Sparks helped with nine timely points and a season-high eight assists, as Kentucky shot 60 percent in the second half on 21 of 35.
Heath had said Arkansas must dominate the paint in order to have a chance to win, but Kentucky scored 38 points in the paint to Arkansas' 28.
Eric Ferguson scored 14 of his season-high 19 points for Arkansas in the second half, and Brewer scored 17 of his 23 in that half, but it wasn't enough.
Kentucky, in whittling a 33-15 deficit to 35-23 by halftime, took advantage of traveling violations called against Ferguson and Darian Townes, as Morris heated up for six quick points and Sheray Thomas added a baseline jump shot.
Morris had 10 points in the first half, as did Arkansas' Jonathon Modica, who finished with 13 points and 6 rebounds.
The Razorbacks, showing perhaps their best patience of the season, shot 14 of 30 in the first half for 46.7 percent, compared to Kentucky's 10 of 26 for 38.5 percent. Arkansas also had fewer turnovers than UK in that half, 7 to 8 (but more for the game, 16 to 14).
In short, the Hogs played so well in the first 20 minutes that the blue-clad fans booed their return to the court for the second half -- a telltale sign of respect.
Wildcats fans' loudest applause in the first half came when the Kentucky women's team was honored during a timeout for having beaten Tennessee 66-63 before 13,689 UK fans last week.
Arkansas started the second half well enough, with Brewer hitting a jumper and then stealing the ball to set up a Dontell Jefferson dunk for a 39-23 lead.
But soon Kentucky began raining 3-pointers, as Ravi Moss, Joe Crawford, Sparks and Thomas found the range and the 'Cats pulled within 46-41.
Ferguson resisted well for Arkansas, making two 3-pointers and a great drive to help the Hogs stay ahead 54-47, but Kentucky shrugged and kept coming until Morris put the 'Cats ahead 60-59 with a three-point play with 6:03 left.
After Kentucky galloped all the way to 70-61, Arkansas made a counter-comeback in the final two minutes.
Ferguson's 3 made it 70-64 and Brewer meshed two free throws for 70-66 with 1:02 to go. A trey by Sean McCurdy kept the Hogs within 77-73 at 18.1.
When Morris missed two free throws, Arkansas had a big chance. But Brewer, rather than taking a pull-up '3', passed inside to Vincent Hunter, who had the ball stripped away by Moss. One Moss free throw later, Brewer buried a 3 to make the score 78-76, Wildcats, with 1.7 ticks left.
But Arkansas had called its last timeout with 1:35 left and could only watch as Rondo took the inbounds pass and, fittingly, scampered away with the basketball.
Kentucky's players, who said they "had to win" Sunday's game, played like it in the second half, if not the first.
"They just played harder than us in the second half," Ferguson said.
Foul trouble kept Hogs center Steven Hill from contesting a key shot or two by Morris down the stretch.
But mostly, the Wildcats caught the same fever Arkansas had in the first half.
Wildcats' Wild Second Half Sinks Hogs
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