Marussia announced on Monday that, despite the 30-year-old having a "valid contract" for 2013 and apparently also 2014, it has agreed to part ways with German Glock to make room for a pay driver.
"Although it is not the path I expected to be taking, I am in fact very excited about what the future holds in terms of my own career and I hope to comment on that very soon," the statement quoted Glock as saying.
An exchange on Twitter between Glock and BMW-contracted driver Dirk Muller indicated a DTM move was indeed on the cards.
"We confirm nothing, we deny nothing, we don't comment at all," a spokesman for the German marque, Jorg Kottmeier, told SID news agency.
Germany's Sport Bild, however, reported that Glock is lined up to test BMW's M3 DTM car at Valencia on Wednesday and Thursday.
Glock was a F1 test driver for BMW in 2007.
He is quoted as saying: "I am very excited to test the (DTM) car, and also to meet up at Valencia with some familiar faces from my past at BMW."
Glock's BMW move is reportedly bad news for Jaime Alguersuari, with Spanish radio Radioestadio claiming the former Toro Rosso was a shoe-in for the seat until Glock's Marussia split.
As for who will replace him at Marussia, international reports mentioned Brazilians Luiz Razia and Bruno Senna as possible candidates.
Russian Vitaly Petrov appears to be a natural contender in theory, but his manager Oksana Kosachenko said her only negotiations are with Caterham.
"It depends on the decisions of the directors of Caterham," Kosachenko told Russia's f1news.ru when asked about Petrov's future. "We are not in negotiations with Marussia."