Former Freiburg striker Nils Petersen has heaped praise on Julian Schuster who is considered the frontrunner to succeed Christian Streich as coach of the Bundesliga club in summer. Streich announced on Monday that he will step down at the end of the season after more than 12 years in charge. Former team captain Schuster, 38, currently an academy coach at the southern German side, has the required licence but is yet to coach at top level. But Petersen told dpa this doesn’t matter because “Julian Schuster was already as a player the biggest extension of a coach on the pitch I have ever seen. “It…