Reading youngster Jem Karacan is staying on-loan to the end of the season at Millwall.
The 19-year-old midfielder has enjoyed an impressive initial month at the New Den, making four appearances and helping the Lions ease clear of the relegation zone.
Karacan's initial deal was due to expire after Saturday's all-ticket clash with Leeds, but he will now also be available for the home game against Carlisle and the final-day trip to Swindon.