By Tom Gott Bayern Munich have been tipped to join the race for Chelsea left-back Ian Maatsen this summer. Maatsen, 22, has impressed since joining Borussia Dortmund on loan in January but, as his loan deal does not include a permanent purchase clause, he will return to Chelsea at the end of the season. He is expected to be made available for transfer this summer and, prior to joining Dortmund, signed a new contract at Stamford Bridge which includes a release clause worth £35m to set up a move away from Chelsea. Whether Dortmund will pursue his signature permanently remains to be seen, but Sky…