Harlequins advanced to their fourth Challenge Cup final after securing a 30-6 win over visiting Grenoble at The Stoop.
The contest was overshadowed however by an incident involving Joe Marler on his first game back from suspension, with the England prop appearing to kick out towards the head of Grenoble hooker Armand Héguy.
Harlequins in the end finished with three tries through Jamie Roberts, Nick Evans on his return from injury and George Lowe to book their place in the final in Lyon.
Grenoble were hit hard by the early losses of Dayna Edwards and Nigel Hunt to injury, as Ben Botica struck off the tee to open the scoring.
Harlequins posed the greater threat in the opening stages and it was the powerful running of Wales centre Roberts which helped them extend their lead, hitting a nice line off Danny Care's short pass to sprint past the cover tackle of Walter Desmaison for the opening try.
Jonathan Wisniewski, who hadn't missed a kick since March 20, hit back for Grenoble only to be countered by Botica, as Harlequins maintained control.
But after a shaky start the visitors were beginning to grow in confidence, adding a second penalty from Wisniewski and beginning to spark things in attack through the good work in particular of their centre Chris Farrell. Harlequins however led 13-6 at half-time.
Evans' introduction was followed by a fine chip and chase try as Harlequins put the result to bed, George Lowe going over late on to cap off a comfortable win.
Tries: Roberts, Evans, Lowe
Cons: Botica, Evans 2
Pens: Botica 2, Evans
Pens: Wisniewski 2
Harlequins: 15 Mike Brown, 14 Marland Yarde, 13 George Lowe, 12 Jamie Roberts, 11 Tim Visser, 10 Ben Botica, 9 Danny Care (c), 8 Nick Easter, 7 Luke Wallace, 6 Chris Robshaw, 5 Sam Twomey, 4 James Horwill, 3 Adam Jones, 2 Joe Gray, 1 Joe Marler
Replacements: 16 Dave Ward, 17 Mark Lambert, 18 Kyle Sinckler, 19 Charlie Matthews, 20 Jack Clifford, 21 Karl Dickson, 22 Nick Evans, 23 Ross Chisholm
Grenoble: 15 Gio Aplon, 14 Xavier Mignot, 13 Chris Farrell, 12 Nigel Hunt, 11 Lucas Dupont, 10 Jonathan Wisniewski, 9 Charl McLeod, 8 Steven Setephano, 7 Fabien Alexandre, 6 Mahamadou Diaby, 5 James Percival, 4 Ben Hand, 3 Dayna Edwards, 2 Arnaud Héguy, 1 Sona Taumalolo
Replacements: 16 Loick Jammes, 17 Fabien Barcella, 18 Walter Desmaison, 19 Mathias Marie, 20 Henry Vanderglas, 21 James Hart, 22 Fabien Gengenbacher, 23 Fabrice Estebanez
Referee: John Lacey (Ireland)
Assistant Referees: Marius Mitrea (Italy), Peter Fitzgibbon (Ireland)
TMO: Jim Yuille (Scotland)