Goals from midfield duo Danny Drinkwater and Andy King cancelled out the Baggies’ opener from forward Saloman Rondon, only for Craig Gardner to level moments after the re-start with a 25-yard free-kick.
Strikers Jamie Vardy and Shinji Okazaki both crashed headers against the crossbar, while substitute Leonardo Ulloa was unable to repeat Saturday’s match-winning heroics as a late chance went begging.
A draw stretched Leicester’s lead at the summit to three points although a victory for second-placed Tottenham at high-flying West Ham tonight would see the north London side hit top spot on goal difference.
A late Fabio Borini strike, meanwhile, earned a precious point for relegation-haunted Sunderland as Crystal Palace’s winless run was extended to 11 matches after a 2-2 draw at the Stadium of Light.
Striker Dame N’Doye opened the scoring before Connor Wickham continued his hot streak of goalscoring form with a second-half double, although Borini ensured that he had the final word.
The 24-year-old’s equaliser, coupled with Norwich’s defeat to Chelsea, was enough to move Sunderland out of the relegation zone at the expense of the Canaries, while Palace stay 14th, nine points clear of the drop zone.
Bournemouth eased their own relegation fears and moved eight points clear of danger with a 2-0 success over south coast rivals Southampton as defender Simon Cook and former Arsenal forward Benik Afobe netted.
Aston Villa’s fans staged a mass walkout in protest at owner Randy Lerner as their seemingly forlorn hopes of survival were dealt another crushing setback following a 3-1 home defeat to Everton. Ramiro Funes Mori, Aaron Lennon and Romelu Lukaku scored for the Toffees.