Arsenal's move for Shkodran Mustafi has reportedly hit a snag as they are unwilling to meet Valencia's £25m valuation of the defender.
The Gunners were thought to be close to making the Germany international just their second high-profile signing of the summer following initial talks between the two clubs.
According to The Mirror, however, Arsenal boss Arsene Wenger will go no higher than £20m for the centre-back, which is short of the sum Valencia are holding out for.
Mustafi is said to have agreed terms to make a switch to the Emirates Stadium, where he will provide much-needed central-defensive cover in the absence of Laurent Koscielny, Gabriel Paulista and Per Mertesacker.
In another twist to the proposed move, it is claimed by the same publication that the Spanish outfit have offered Aymen Abdennour - previously linked to Barcelona - to Arsenal, but Wenger is only interested in thrashing out a deal for Mustafi.
The Gunners shipped four goals in their opening game of the season at home to Liverpool on Sunday, with makeshift duo Calum Chambers and Rob Holding - the latter a £2.5m signing from League One Bolton Wanderers earlier this summer - filling in at the back.