Mercedes team boss Ross Brawn says Michael Schumacher not to blame for problems . Seven-time world champion retired in third race of his F1 comeback in Malaysia . Brawn expects the 41-year-old to keep showing improvement in Chinese Grand Prix . The German driver has been plagued by reliability issues since returning from a broken leg suffered at last year's Australian GP.
Mercedes team boss Ross Brawn says Michael Schumacher not to blame for problems . Seven-time world champion retired in third race of his F1 comeback in Malaysia . Brawn expects the 41-year-old to keep showing improvement in Chinese Grand Prix . German has been outperformed by young teammate Nico Rosberg so far this year .