Roscoes went ahead after half-an-hour, Sam Collin grabbing the goal for Lee Paterson’s side, who lead 1-0 at the break.
Tavern brought themselves level courtesy of Thameur Dridi’s penalty in the 55th minute and Dan Thomas’ side took the lead for the first time through Jack McFarlane’s bullet header with just five minutes left on the clock.
The win was sealed thanks to a last-gasp goal from Kristian D’Rosario after good work from Dan Blanchard.
Thomas said: “To win against top of the league who were unbeaten is a big result for us.”
McFarlane was Tavern’s man of the match.
Paterson said: “This was the worst performance I’ve seen from us for a long time.
“Only Jack Worthy and Liam Rowley played well for us.”
Angel Reserves battled back from a goal down to beat Saints 3-1.
A Rafal Jackow pen put Saints ahead, but Angel battled back with man of the match Tom Sixsmith hitting two and Jake Moore firing in.
Eastfield Athletic won 3-2 against Fylingdales despite going 2-0 down.
Dales were well ahead but Athletic battled back and goals from Tom Swayne, Jonny Hunter and Matty Hillman sealed the points for Andy Thorpe’s side.
Adam Martin was Athletic’s man of the match.
Trafalgar were made to battle hard for the points as they beat Cayton Corinthians 4-1 in Division One.
Cayton led through Luke Chambers’ strike, but the sides went in level at 1-1 heading in at the break.
Traf pulled away in the second half as goals from Jamie Patterson, Sam Garnett, Tyler Richardson and Dan Exley found the back of the net for Niall Gibb’s side.
Richardson and young centre-back Connor Avison shone for Traf while Cayton player-boss Steven Frederiksen singled out Nicko Dunn and new signing Ciaran Moss as his side’s star men in a battling display.
Newlands hammered West Pier 8-0 to stay in the title race.
Brad Marshall bagged a hat-trick for Dan Sheader’s side, striker Zac Hansen continued his fine run of goal with a brace, including one stunning strike from the edge of the box, and their scoring was wrapped up by goals from Rob Whitehad, Mark Wade and Brad Rowley.
Sheader singled out right-back Liam Mintoft as his team’s man of the match, while Pier manager Paddy Parke praised the efforts of his under-strength side with Jayden Rodgerson and Dave Oxley their star men.
Angel claimed a 5-0 victory against a depleted Valley side.
Angel’s goals came from Martin Cooper, Gary Thomas, Robbie Scarborough and joint men of the match Neil Thomas and Lloyd Henderson.
Boss Ben Kristensen was proud of his side’s efforts despite defeat.