Ayoze Perez eased Newcastle's relegation fears as the Magpies ended their away win drought at Leicester.
The striker's eighth goal of the season earned the Magpies a 1-0 victory and their first victory on the road since December.
It moved Newcastle up to 13th, 10 points clear of the Premier League's relegation zone, having played up to two games more than their rivals with four matches remaining.
Salomon Rondon's splendid first-half free kick hit the bar for Newcastle and Jamie Vardy missed the Foxes' best chance when he lifted over late on as the hosts' four-game winning run ended.
Defeat was also a major dent in the race for seventh and a possible Europa League spot with Watford, Everton and Wolves all ready to take advantage over the weekend.
The Foxes had started well enough and the teams traded early half chances through Jamaal Lascelles and Jamie Vardy before Leicester took control.
Ben Chilwell and Harvey Barnes were threats but the Magpies almost took the lead out of the blue after 15 minutes.
Wes Morgan fouled Perez and Rondon crashed a brilliant curling free kick against the crossbar from 30 yards.
The Foxes quickly regained their composure and Chilwell forced Martin Dubravka into a low save after 21 minutes.
Dubravka also gathered Barnes' sharp effort after the winger's strong run with Newcastle having to rely on their counter attacking threat.
But the Foxes, who were sloppy at the back, had given some encouragement and the Magpies cashed in to grab the winner after 32 minutes.
It was poor from Leicester but Newcastle were clinical as Matt Ritchie's wicked cross found Perez who ran off the back of the unsighted Morgan to glance in a terrific near-post header across Kasper Schmeichel.
Miguel Almiron then forced Schmeichel into a low stop as the visitors pushed for a surprise second.
It had been a textbook counter-attacking away performance from Benitez's side and they began the second half on the front foot - only for Perez to horribly miscue Rondon's cross.
Leicester, with just two clean sheets this year, were ragged and Almiron sliced well over just before the hour as the visitors threatened again.
Slowly, though, the Foxes built momentum without finding the killer pass with Vardy well marshalled by the Magpies' defence.
A fifth straight win would have equalled Leicester's best run in the top flight since 2017.
But their hopes began to fade and James Maddison curled a free kick over with 15 minutes left.
Time was running out and Schmeichel needed to be alert to save at Perez's feet after the striker turned Chilwell.
Yet Vardy should have levelled with 10 minutes left when he was slipped in by Youri Tielemans and could only scoop over with Dubravka to beat.