Middlesex 534 (Geddes 137, Green 3-54) beat Leicestershire 205 (Patel 51, Sharma 4-43) and 202 (Cornwell 3-60) by an innings and 127 runs
Division Two leaders Leicestershire crashed to their first Rothesay County Championship defeat of the season by an emphatic innings and 127 runs as Middlesex handsomely avenged their opponents' victory at Lord's in May.
Following on after being dismissed for 205 in their first innings in reply to Middlesex's 534, Leicestershire were bowled out for 202 in their second innings, beaten with more than a day to spare.
Rookie fast bowlers Naavya Sharma and Noah Cornwell played key roles in a Middlesex attack lacking skipper and leading wicket-taker Toby Roland-Jones after centuries for Sam Robson and Ben Geddes against a depleted Leicestershire attack had set up the match for the visitors. Geddes, dropped on 11, went on to score 137.
Sharma's six wickets in the contest included a career-best first-innings four for 43, while left-armer Cornwell's four included three for 60 in the second innings, another career-best, although both were playing in only their third first-class matches.
Leicestershire's 33-point lead at the start of this round will limit the damage inflicted by this loss. Middlesex's third win gives them a chance to finish among the promotion contenders.
Only a rearguard effort in the morning that saw them almost double their overnight score had kept Leicestershire from being made to follow on sooner after slipping to 99 for eight before Monday's close.
Roman Walker made 40 not out and rookie fast bowler Sam Wood 33 in forcing Middlesex to bowl 37 more overs to pick up the last two wickets. Tom Helm, who missed the early Championship rounds through injury, finished with three for 30.
In addition to a career-best three for 73 with the ball, Walker shared partnerships of 42 for the ninth wicket with Chris Wright and 64 for the tenth with 20-year-old seamer Wood, who bowls right arm but bats left-handed.
Helm moved one away to have Wright caught behind and Wood, who looked no mug with the bat as he drove Zafar for six over long-on, nicked off to Ryan Higgins, wicketkeeper Joe Cracknell holding his fifth catch of the innings.
Middlesex might have chosen not to enforce the follow-on with a view to adding a few more to their 329-run lead before giving the home side at least some incentive to pitch their ambitions higher than salvaging a draw.
In the event, perhaps mindful of getting their fingers burned when they set Northamptonshire a target at Wantage Road last week, they stuck with convention and sent their chastened opponents out again.
And what a good decision it was. Having been 82 for two before the collapse came on Monday, Leicestershire had lost their first six wickets for 80 by tea.
It seemed the resilience shown by the tail earlier in the day had counted for nothing as Sol Budinger edged Helm to second slip before Higgins came on as first change at the pavilion end and induced a tame return catch from Rishi Patel with his second ball.
Cornwell then struck in consecutive overs, bowling Liam Trevaskis, Leicestershire's stop-gap No 3, with one that nipped back before making one climb to have Peter Handscomb caught off the splice by short leg Ben Geddes.
Ben Green was dropped by Geddes in Cornwell's next over but added only one more run before he drove at Higgins to be caught behind for 10. Higgins then took a catch at slip as left-armer Zafar found some bounce and the edge of Lewis Hill's bat to leave Leicestershire 80 for six.
Ben Cox and Logan Van Beek at last showed some grit, adding 58 in just under 16 overs before the dismissal of Cox, caught at leg gully at the second attempt fending off Sharma, who dismissed Walker with another short ball fended to short leg.
Wright flung the bat for 26 off 20 balls before a top-edge saw him caught at mid-on, Wood had some fun with two towering sixes in his 27 before another top-edge had him caught behind, and Van Beek finished with a defiant unbeaten 36 but Leicestershire's fate was all but sealed by that point.
