Wayne Rooney continued his return to form at Anfield on Sunday, striking 12 minutes from time to earn Manchester United a 1-0 win against fierce rivals Liverpool.
In a largely tepid contest lacking quality on both sides, Rooney reacted quickest when Marouane Fellaini's header rattled the crossbar - ensuring United a fourth consecutive victory over the Merseyside outfit.
Liverpool - still in flux under Klopp and struggling for consistency - had the better of the first-half chances but were made to rue missed opportunities from the likes of Adam Lallana and Jordan Henderson.
Louis van Gaal's men also looked to have reverted to their goal-shy ways of recent weeks, showing little sign of the renewed attacking vigour on show during Tuesday's 3-3 draw at Newcastle United.
However, when Fellaini climbed highest to head a Juan Mata cross against Simon Mignolet's crossbar, Rooney made the most of sloppy Liverpool defending to hammer in the winner and maintain his goalscoring streak.
After a season of criticism for the United skipper, Rooney has now scored five goals in his last four outings, leaving Klopp and his Liverpool side to lament their lack of killer instinct.
While United were unchanged from Tuesday's draw on Tyneside, Liverpool brought in Lucas Leiva for Jordon Ibe following their 3-3 draw against Arsenal.
And, amid a frenetic start, the Brazilian's clever pass allowed Lallana a header on target before Roberto Firmino sent the rebound wide following a smart stop from David de Gea.
In a traditionally fiery encounter, tempers flared just 15 minutes in when Fellaini and Lucas squared up, but slack play and misplaced passes continued to hamper both sides inside the opening half-hour.
Henderson fired wide after neat interplay involving Lucas and Firmino, with the latter seeing penalty appeals turned down when he went down under minimal contact from Anthony Martial.
United's difficult half ended with Ashley Young limping off - the full-back replaced by Cameron Borthwick-Jackson three minutes before the break.
Liverpool remained the more vibrant in possession but saw Rooney burst clear on goal after hesitation from Nathaniel Clyne, only for another attack to predictably peter out.
At the other end, De Gea saved Emre Can's low drive with his legs as chances began to flow, Martial the next to go close when he dragged a shot wide before the hour mark.
In the final half-hour, Henderson side-footed a shot straight at De Gea from the edge of the area, while the Spaniard was called on again to deny Can and Firmino in quick succession.
Van Gaal introduced Memphis Depay and Mata - last season's two-goal hero in this fixture - with the Spaniard's delivery leading to the game's defining moment 12 minutes from time.
Fellaini, whose contribution had been limited, showed his aerial threat, with Rooney reacting smartly to beat Mignolet and maintain United's upturn in fortunes despite a relatively mediocre display.