Stephy Mavididi scored twice as Leicester extended their lead at the top of the Sky Bet Championship to three points with a 3-2 win against Birmingham at St Andrew's.Leicester fans wore Jamie Vardy masks in support of their absent striker, whose wife Rebekah lost a court case against Blues boss Wayne Rooney’s wife Coleen after a judge ruled Vardy’s wife passed on information about Rooney to the press.A dramatic start saw three goals in the first 22 minutes.Birmingham created the first opening but midfielder Jordan James’ low, bouncing drive was straight at goalkeeper Mads Hermansen.Blues forced two early saves from the Danish stopper, who blocked Siriki Dembele’s shot with his legs then tipped over Krystian Bielik’s back header from Marc Roberts’ long throw-in.Leicester took the lead from a speedy breakaway from a Blues corner in the 10th minute – after James Justin’s sliced clearance cannoned off his own post.Abdul Fatawu sped away, and in a two-v-one, squared to Mavididi to dink the ball over advancing keeper John Ruddy for a classy finish.Mavididi was booked for climbing the advertising hoarding and goading Birmingham fans in his celebration.Rooney’s side were level after 15 minutes when James found the bottom corner with a low shot after Dembele squared to Ivan Sunjic, who supplied the killer pass.Leicester regained the lead in the 22nd minute in another lightning counter-attack which started on the edge of their own box.This time Ricardo Pereira dispossessed Juninho Bacuna and Fatawu again raced goalwards, releasing Kiernan Dewsbury-Hall to round Ruddy and slot into an empty net for his seventh goal of the season.Leicester went close to extending their lead when Dewsbury-Hall crossed deep inside the area but Patson