Newcastle United are being linked with a possible move for Liverpool pair Peter Crouch and John Arne Riise.
This summer will be Keegan's first opportunity to enter the transfer market on behalf of Newcastle since he ended his first spell as Magpies' manager nine years ago.
He is keen to mould his squad for next season and is therefore expected to make some significant signings this summer.
Norwegian left-back Riise has been linked with Newcastle for some time. Keegan has only Jose Enrique as a specialist in that position, and Riise can also provide cover in midfield.
Crouch on the other hand just wants the chance to play regular first-team football.