The opening round of the second half of the 2014 ADAC GT Masters season at the Slovakia Ring (8th - 10th August) will have to proceed without the participation of Mercedes-Benz man Heinz-Harald Frentzen (HTP Motorsport). The former F1 world championship runner-up is to undergo an operation on his knee ahead of the race weekend in Slovakia. Frentzen's doctors have deemed the operation fairly urgent and have booked him in at short notice. Consequently, he will be unable to drive his Mercedes-Benz SLS AMG GT3 in the two races on Saturday and Sunday.

"This is a hangover from the accident I had in my Jordan-Mugen Honda in the 1999 Canadian Grand Prix," said the 46-year-old veteran from Mönchengladbach. It has not yet been decided who will be Luca Stolz's co-driver in the gullwing fielded by HTP Motorsport at the Slovakia Ring. The team is making strenuous efforts to find a "quick and high-calibre" replacement.