Northampton captain Dylan Hartley's Lions tour hopes are in doubt after he was sent off for dissent during his side's Aviva Premiership final defeat at Twickenham yesterday.
The England hooker was dismissed during first-half injury-time by referee Wayne Barnes. Hartley had been warned about his conduct just two minutes beforehand.
He could now face a minimum six-week ban. English RFU disciplinary bosses are unlikely to take a lenient view, considering he has already served three previous suspensions during his firebrand career.
Hartley can expect a disciplinary hearing early this week. The Lions leave London for Hong Kong tomorrow, with Hartley currently one of three hookers among a 37-man squad.
Lions head coach Warren Gatland, a strict disciplinarian, could now launch an immediate search to replace Hartley. Ireland and Ulster hooker Rory Best would be favourite to join the trip.
An incident-packed final saw Leicester skipper Toby Flood forced off with concussion before the break, while Northampton assistant coach Dorian West, speaking during a pitchside television interview, accused Leicester boss Richard Cockerill of "intimidating" match officials.
The game ultimately went the Tigers' way as wings Niall Morris – from Dublin – and Vereneki Goneva, lock Graham Kitchener and Lions centre Manu Tuilagi scored tries, with Flood booting a penalty and a conversion and his replacement George Ford kicking four penalties.
But Northampton, despite being reduced to 14 players for half of the encounter, conjured tries for Stephen Myler, Ben Foden and Lee Dickson, with Myler adding one conversion.
Leicester deservedly lifted their first Premiership title since 2010 in front of an 81,000 crowd, but the result will be overshadowed by Hartley's red card and its potential repercussions for the Lions.
Scorers – Leicester: N Goneva, M Tuilagi, N Morris, G Kitchener try each; T Flood con, pen; G Ford 4 pens.
Northampton: S Myler con, try; B Foden, L Dickson try each.
Leicester: M Tait; N Morris, M Tuilagi, A Allen, N Goneva (M Smith 74); T Flood (G Ford 23), B Youngs (S Harrison 74); L Mulipola (F Balmain 75), T Youngs (R Hawkins 67), D Cole (M Castrogiovanni 67), G Kitchener (E Slater 55), G Parling, T Croft, J Salvi, J Crane (S Mafi 72).
Northampton: B Foden (TG Pisi 67); K Pisi, J Wilson, L Burrell, J Elliott (M Haywood 40); S Myler (M Roberts 67), L Dickson (R Lamb 67); S Tonga'uiha (M Waller 55), D Hartley, B Mujati (T Mercey 56), C Lawes, C Day (GJ van Velze 60), P Dowson (B Nutley 67), T Wood, S Manoa.
Referee: W Barnes (England)