With time almost up Schmeichel headed in off the crossbar - before substitute Chris Wood made sure the ball went over - to snatch a 1-1 draw and deny Yeovil who would have climbed out of the relegation zone with victory.
Joe Ralls' 22nd-minute goal had given the Glovers the lead until Schmeichel finally broke their resistance to extend the Foxes' unbeaten run to 13 games.
Second-placed Burnley nonetheless profited on Leicester's slip-up as they beat Doncaster 2-0. Sam Vokes fired in a penalty shortly after half-time before Junior Stanislas made sure the Clarets moved three points behind Leicester in the title race.
QPR moved up to third as they ended Wigan's stunning run 1-0 thanks to Yossi Benayoun's 16th-minute goal.
Benayoun saw red late on but Harry Redknapp's men held on against a Latics side that had won nine of their past 10. QPR's hopes of automatic promotion appear remote, however, as they remained 10 points adrift of Burnley.
Derby were unable to hold on after Patrick Bamford gave them a first-minute lead to lose 2-1 at Ipswich.
A Jonathan Williams screamer levelled the match on 68 minutes before defender Christophe Berra won it in injury time. Victory moved Mick McCarthy's side two points from the play-off places as those just inside it had a night to forget.
In addition to Derby and Wigan's defeats, sixth-placed Reading suffered a forgettable 3-1 home reverse to Barnsley.
The Tykes began the night rock-bottom but were gifted a 16th-minute lead when Chris O'Grady easily intercepted a poor back pass and laid off the ball for Stephen Dawson to score.
Pavel Pogrebnyak levelled from the penalty spot moments later but that was as good as it got for the Royals. Reuben Noble-Lazarus sent Barnsley back ahead on 53 minutes before Dale Jennings smashed in a third to prise the Yorkshire strugglers off the bottom.
Millwall replaced them in last place after they lost 3-2 to Birmingham at the Den.
Jordon Ibe's opener was cancelled out when Steve Morison's tight-angled shot went in with help from away defender Paul Robinson.
Headers from Andrew Shinnie and Nikola Zigic gave Birmingham the breathing space they needed when Simeon Jackson slotted a late penalty.
Charlton opened a three-point gap over the relegation zone as they beat managerless Nottingham Forest 1-0.
Jordan Cousins struck the winner nine minutes from full-time in Forest's first match since Billy Davies was sacked. Forest are now winless in eight games although stay two points outside the top-six thanks to the defeats of the teams above them.
Another crisis club, Leeds, were pummelled 4-1 at Bournemouth.
Cherries strikers Yann Kermorgant and Lewis Grabban both netted doubles before Ross McCormack pulled back a late one for well-beaten Leeds.
Striker Rudy Gestede scored an injury-time equaliser as Blackburn snatched a thrilling 3-3 draw at Watford.
The hosts thought they had wrapped up the points moments earlier when substitute Cristian Battocchio ran clear of the away defence and scored.
A see-sawing contest started with Marco Cassetti giving Watford a fourth-minute lead before David Dunn and Craig Conway wrestled the lead to Blackburn. Troy Deeney levelled from the penalty spot before the late drama.
Albert Adomah twice equalised as Middlesbrough drew 2-2 at Huddersfield. Adam Hammill and Nakhi Wells had put Town ahead.
Leon Best slid in an injury-time winner as Sheffield Wednesday beat promotion-chasing Brighton 1-0 while a 16th-minute David Wheater header was enough for Bolton to overcome Blackpool by the same scoreline.