The 24-year-old, who has eight caps for Mali, has not featured for the Hoops since an emphatic 3-0 loss to Liverpool at Loftus Road in the final game of 2012 in the Premier League.
Redknapp brought in Jermaine Jenas to strengthen his central-midfield options during the transfer window, with Park Ji-Sung, Esteban Granero and Stéphane Mbia already vying for a spot in the manager’s starting line-up.
The Hoops boss says he rates the African midfielder but warned Diakité that he must prove his worth in order to win his place back in the team.
“His form dipped a little bit before he went away. The Liverpool game was a disappointment,” said Redknapp.
“And now there’s Jermaine Jenas, there’s Park, there’s Granero and Mbia – we’ve got a group of them central midfielders.
“But Samba’s a good lad, and I like him and he’s training well. I guess he could be in the team anytime.”
Diakité has made 14 appearances for QPR after completing a £3.5m move to Loftus Road from Lille last summer.
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