Brentford want to sign Nuremberg winger Robin Hack if they lose Said Benrahma.
The 21-year-old Germany U21 player is a top target should their £25m-rated winger move to the Premier League this summer.
Hack came through the youth ranks at Hoffenheim before joining Nuremburg in the Bundesliga 2 last year.
He scored 10 goals in 31 appearances last season.
The Bees are preparing for the potential losses of Benrahma and Ollie Watkins and want in excess of £50m for the pair.
Benrahma is of interest to a string of Premier League clubs including Aston Villa and West Ham.
Brentford also want to strengthen with a new central midfielder and right-sided centre-back this summer.
They will also look to sign a left-back if a buyer comes forward for Rico Henry.
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