Watch TSG Hoffenheim vs Borussia M'gladbach Live Streaming
Watch TSG Hoffenheim vs Borussia M'gladbach Live StreamingManager Arsene Wenger had spoken of his complete confidence in the "massive potential" of the young Pole in the build up to the first leg of the last 16 tie.
However, Fabianski - who was less than impressive in last season's FA Cup semi-final at Wembley and then found himself exposed in the fourth-round defeat at Stoke last month - was once again unconvincing.
First, the 24-year-old pushed Silvestre Varela's cross into his own net before then giving away a free-kick when he picked up a back-pass from Sol Campbell which led to Porto's second goal.
Fabregas, though, insisted the whole dressing room was behind the keeper, who looks set to be between the posts again for the visit of Sunderland on Saturday.
"He is a very good keeper," said the Arsenal captain.
"He had his chance and sometimes it doesn't go your way.
"But we will stand up and support him until the end because he is a good character and I am sure he will be back."
