Grayson said Dallaglio instigated spat with Spencer

Wasps beat Saints 30-13 at the Ricoh Arena on Sunday to set up a final against the Tigers.

Grayson said: "Leicester's forwards were fairly overwhelming against Llanelli. I think they are favourites.

"But it is going to be a good game. Wasps won't fall away physically, however they might have to go up a notch tactically."

Northampton surged into a 13-0 lead in the first 17 minutes in Coventry before conceding 30 unanswered points.

Grayson admitted: "You cannot defend for 75 minutes in a game - it is just not possible.

Lawrence slapped Carlos out of the blue and Carlos lost his temper, as you would do Paul Grayson Northampton coach

"We soaked up wave after wave of attacks, but it was inevitable Wasps would take the lead at some point.

"They are big, fast and strong, and they keep coming at you."

Grayson added that Lawrence Dallaglio had instigated an early spat with Carlos Spencer.