Skysports.com reports that Celtic look like missing out on Argentine duo Juan Carlos Menseguez and Marco Ruben.
Bhoys boss Tony Mowbray wanted both players involved in their UEFA Champions League play-off first leg clash with Arsenal.
Ruben is currently with Spanish side Villarreal, but now up to half-a-dozen Premier League clubs are understood to be in talks with Ruben's representatives about a deal.
The 22 year old's English representative Barry McIntosh admitted Celtic had shown an interest.
"Marco is honoured by the interest from Celtic and obviously such a move would be of interest to him," McIntosh told skysports.com.
"But at the moment a deal has not been concluded and we understand there is interest now arising in England."
Mowbray had also hoped to sign Menseguez, a player he signed whilst in charge at West Bromwich Albion last season.
"Diego Simeone, San Lorenzo's new boss, likes Menseguez a lot," McIntosh revealed.
"It may now be difficult for him to seal a move back to Europe."