Worcestershire 113 for 4 (D'Oliveira 51*, Rehan 2-25) beat Leicestershire 112 (Mir 4-22) by six wickets
Worcestershire Rapids kept alive their hopes of qualifying for the knockout stages of the Vitality Blast by ending a run of four straight defeats in the North Group with a comfortable six-wicket win over Leicestershire Foxes.
Skipper D'Oliveira's unbeaten 51 then saw his side home in the 17th over to raise their points haul to 10 as they bid to build on their four back-to-back wins at the start of the competition and clinch a top-four finish.
Australian wicketkeeper-batter Peter Handscomb, not originally part of the Foxes' Blast plans but drafted in as injury cover with batter Lewis Hill and overseas pace bowler Naveen ul-Haq among those absent, top-scored with 36 from 20 balls and Rishi Patel made 27 from 22 but the next-highest score was Wiaan Mulder's 11.
Having been put in on a slow pitch, the Foxes looked set to post a competitive total despite losing Nick Welch to the fourth ball of the innings, racking up 56 runs in the powerplay for that one loss.
Welch miscued a big drive against Dillon Pennington but after Patel had launched a free hit over the long-on boundary following a Josh Tongue no-ball, Handscomb showed the Foxes what they had been missing by plundering two sixes and three fours.
But everything fell apart for the home side just as soon as the Australian was out in the eighth over, bowled by D'Oliveira's first ball as he was beaten trying to work to leg. The second-wicket pair had blitzed 64 in 39 balls but no other partnership exceeded 13 as one wicket followed another in rapid succession.
The next over saw Mir - brought back by the Rapids as a replacement for the injured Michael Bracewell - dismiss Colin Ackermann and Patel in the space of three deliveries as the Foxes skipper was caught behind off an inside edge and Patel was leg before trying to slog-sweep after hitting two sixes in his 22-ball 27.
Louis Kimber was bowled giving himself room to drive Mitchell Santner before Rehan Ahmed holed out to long-on. Mir took two in two balls, having Tom Scriven caught in the deep and bamboozling Mike Finan with a first-ball googly.
Mulder's ramp was well caught by a diving Pennington before the rout ended with Callum Parkinson trying to lob a ball from Pat Brown over D'Oliveira at extra cover only to be foiled by an athletic leap and one-handed catch.
The last nine wickets fell for 46 as the Foxes were out in 18.2 overs, which can only be described as miserable, much as Mir and D'Oliveira had bowled well, requiring the visitors to score at less than six an over to win the game.
Although the sky was darkening as they began their innings, the Rapids knew they could afford not to take risks so long as they kept in front of the DLS calculation, with just five overs needed to be bowled by the Foxes to make it a match.
It thus did not matter that their 37 for 1 from the first six looked modest next to the home side's 56 for 1, Jack Haynes the one loss as he clipped a ball from Matt Salisbury into the hands of Kimber on the leg side.
Leicestershire gave themselves a faint glimmer of hope as Santner found the fielder on the long-off rope and Adam Hose bottom-edged a ball from Rehan into his stumps, the Rapids losing wickets in consecutive overs, but at 66 for 3 from 10, they were still in front on DLS with thunder rumbling nearby.
Kashif Ali became a second victim for Rehan when he edged to short third man in the 15th over but by then only 21 runs were needed from 35 balls. Rain now was falling but the umpires sensibly kept the players on the field long enough for Ben Cox to sweep Ackermann for four and D'Oliveira to hit Finan for a mighty six over long on and a lofted four over extra cover to clinch victory with 22 balls to spare.