The 18-year-old midfielder is currently on-loan at Ryman League Whitehawk FC and he has been in stunning form with 11 goals in 11 games.
Wallace, who is highly regarded after being plucked from non-league by Pompey in 2011, is being tracked by a number of clubs.
Sky Sports understands that Chelsea, Liverpool and Stoke City have all had scouts take in Wallace's recent progress, and it is little surprise that he has impressed.
The clubs interested in Wallace have also been alerted to the fact that as with every Pompey player, due to their financial situation - they are all on month-to-month deals.
This means Wallace will be free to leave at the end of December with only a minimal amount of compensation due to the League One club - given he has only been at Fratton Park for just over 12-months.
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