Sakho the mystery man?
Apart from admitting his interest in Swiss international Ricardo Cabanas, who has reportedly rejected a move to Wolfsburg as he favours a move to Wearside, McCarthy has not been drawn in on naming other targets.
Yet he has now admitted that one of the several trialists he has invited over to train with the Black Cats has impressed him. Speaking to the Shields Gazette McCarthy said: 'There is one in particular who has stood out, and I'm not going to tell you his name.
'They have all done well while they've been here. Sometimes you get trialists in and after five minutes you wonder what they're doing, but that's not been the case this time.'
Amongst the trialists known training on Wearside is 28 year old Norwegian defender Christian Steen, who has already rejected offers from his home country in order to try and win a deal at The Stadium of Light.
However the player McCarthy is most likely to be referring to is Senegal international forward Lamine Sakho.
The forward can play in midfield or attack and has Premiership experience, playing regularly under ex-Sunderland boss Peter Reid at Leeds whilst on loan at Elland Road during the 2003-04 campaign.
The tricky St Etienne forward missed his club's match against Metz on Wednesday in order to try and impress manager McCarthy, and if reports are to be believed, he could well be the newest addition to the Sunderland squad.
Win FREE pizza with Vital Football!
Select your team and get 50% off if they score twice.
Register on this site via the drop down menu and leave feedback to this story below or to join in the debates on the forum.
Go on, get vitalled!