Cockerill’s side lost Toby Flood and Dan Cole to the sin bin for offences he didn’t deem worthy of yellow cards while no action was taken on Toulon’s Bakkies Botha after he took out Marcos Ayerza.
“The boys are down but it was a massive effort in a huge game. We came up just short and the margins were tiny,” he said.
“I think they [yellow cards] were harsh. Flood’s tried to catch the ball and it was three points and a yellow card. Maybe it’s a penalty but why stick guys in the bin?
“Cole is a penalty but are they going to score? No. But he’s in the bin and that’s harsh. Especially when you see Bakkies Botha lift his knee and get Marcos [Ayerza] off the field with a suspected broken clavicle.
“There’s lots of things in the game that they’re really fussy on and then there are things that just make you shake your head.”
In a game of such fine margins, it was the boot of one of the most respected out halves in English rugby history who put paid to Leicester’s hopes. Wilkinson outscored former England team-mate Toby Flood as the French Top 14 leaders squeezed through.
“I have lots of experience of playing against Leicester,” said Wilkinson, who slotted over all six of his penalties. “They can control matches. We had to maintain the effort and discipline during the match... and remain solid for 80 minutes. There are good European teams [in this stage of the competition], to be in the semis is a real pleasure. But the next game will be even harder.”
Three penalties from Flood gave the Tigers an early 9-0 lead before two successful kicks from Wilkinson hauled the hosts to within three at half-time.
Two subsequent penalties from Wilkinson handed Toulon their first lead at 12-9 before Flood hauled the visitors level. Toulon then moved six clear thanks to Wilkinson but Flood gave Leicester hope with his fifth only for Wilkinson to wrap up proceedings with a late drop goal.
Toulon: Pens: J Wilkinson 6. Drop goals: J Wilkinson.
TOULON: D Armitage, R Wulf, M Bastareaud, M Giteau, A Palisson, J Wilkinson, S Tillous-Borde; A Sheridan, S Bruno, C Hayman, B Botha, N Kennedy, JF Fernandez Lobbe, S Armitage, C Masoe.
Replacements: M Mermoz for Bastareaud (79), V Martin for Palisson (68), G Jenkins for Sheridan (58), M Ivaldi for Bruno (56), J van Niekerk for S Armitage (74).
Leicester: Pens: Flood 5.
LEICESTER: M Tait, N Morris, M Tuilagi, A Allen, A Thompstone, T Flood, B Youngs; M Ayerza, T Youngs, D Cole, E Slater, G Parling, T Croft, J Salvi, J Crane.
Replacements: M Castrogiovanni for Thompstone (67), L Mulipola for Ayerza (54), G Kitchener for Slater (65), T Waldrom for Croft (39).
Referee: George Clancey (RFU).