Wilfred Ndidi’s close-range finish 22 minutes in put Leicester City ahead on Filbert Way before Jamie Vardy made amends for his missed penalty at the end of the first half with a 65th-minute header.
The 37-year-old’s 17th goal of the season came after a barrage of Baggies chances – the visitors denied by heroic goal-line clearances and fantastic saves – before Jed Wallace’s breakaway finish created a climactic finish.
Valiant defending was required to get Enzo Maresca’s men over the line – sparking scenes of real jubilation at full-time, with the Foxes nudging themselves closer to the finish line.
Three huge matches await for Leicester, who next welcome Southampton to King Power Stadium on Tuesday night in what promises to be another significant night in the second tier.
This nerve-shredding race continues to throw up twists and, despite a Baggies onslaught in each half on Saturday, the Foxes emerged with a precious victory to take them to 91 points. That’s two more than second-placed Ipswich Town and four ahead of Leeds United in third – with the division’s top three all having three games left. Southampton could go level on 87 points with Leeds with a win at Cardiff City later on Saturday.