Surrey 143 for 1 (Evans 81*, Jacks 56*) beat Hampshire 138 for 8 (Holland 65, Topley 4-20) by nine wickets
Reece Topley returned to the Ageas Bowl to haunt depleted Hampshire as Surrey remained top of the Vitality Blast South Group with a nine-wicket win.
England white-ball international Topley returned career-best figures of 4 for 20 to restrict his former county to 138 for 8. Then, Will Jacks (56) cracked his third consecutive fifty and Laurie Evans clubbed 81 not out in a 118-run partnership for the second wicket, as already qualified Surrey all but booked a home quarter-final by easing to victory with 28 balls to spare.
Hampshire were forced to leave out four players who were self-isolating due to coming into contact with an individual with Covid symptoms.
The players, along with members of the coaching staff, are awaiting test results and should they come back negative, will be in contention to face Middlesex on Sunday.
A Hampshire statement said: "On the advice of our medical team a number of players have been withdrawn from today's squad.
"This is as a precautionary measure and they are self-isolating while awaiting the results of a COVID-19 test after coming into contact with an individual who has reported symptoms."
As a result, they named an unexperienced XI which included Felix Organ, Tom Scriven, Calvin Harrison and Scott Currie - who had previously made six T20 appearances between them.
Hampshire, who had lost their last five matches in the Blast, then lost the toss and lost a wicket first ball, having been stuck in.
Topley spent three injury-plagued seasons at the Ageas Bowl, but returned with a bang as he splattered George Munsey's stumps with his first delivery.
Organ drove and pulled a pair of boundaries before he was stumped off Jacks to leave the hosts on 11 for 2.
Surrey's leading Blast wicket-taker Dan Moriarty then left Hampshire reeling at 50 for 4 with two quick wickets.
The left-arm spinner had James Vince, who had threatened to break free with 27, stumped before Tom Scriven was lbw, Moriarty returning figures of 2 for 19.
Just as Hampshire looked set to repeat their showing against Essex, Ian Holland and James Fuller combined to take their side towards respectability with a stand of 75.
USA international Holland's previous format best was an unbeaten 36 against Sussex earlier in the campaign, but led the recovery with an impressive 65.
His innings was shaped by clever running but it was his clean three sixes - two straight and other picked up over mid-wicket - which caught the eye as he reached his half-century off 38 balls with a swept four.
After Fuller had stepped on his own wicket for 19, Topley returned to make sure Surrey regained control in the death overs.
The left armer had Holland caught at short third man and Harrison lbw in successive balls, before Currie drilled to Rory Burns at extra cover.
Needing 139 to win, Surrey lost Jason Roy in the fourth over, caught at mid-off to hand Organ his maiden T20 wicket.
But Jacks, on the back of scores of 55 and 65 against Middlesex and Sussex, barely flinched as he scored freely, crashing six fours and a six over midwicket in his 29-ball fifty.
With Lewis McManus undergoing surgery for appendicitis, Vince took the gloves but was not overly used as the ball rarely beat the bat.
While Jacks seemingly slowed down, Evans moved through his innings with a crescendo, with a six whipped off his legs and a driven slash taking him to his half-century in 34 deliveries.
The Jacks and Evans partnership moved past 100 in 66 balls, before they knocked off the remaining runs in rapid style - with back-to-back sixes off Harrison completing a sixth straight Surrey victory.