Injuries to Alex Pritchard and Timm Klose could force Norwich City boss Daniel Farke into the transfer market.
Defender Klose and midfielder Pritchard were both injured in the pre-season friendly with Cambridge United and will miss the start of the new Championship season.
Farke refused to be drawn on potential targets but told BBC Radio Norfolk that reinforcements may be required.
"It would help when you look at our personnel situation," he said.
"It's not such a big squad and because of the important injuries to Pritchard and Klose, and because [Ivo] Pinto and [Wes] Hoolahan were out nearly the whole of the pre-season, we could need some improvements.
"If not, I try to give my best to the guys who are there."
Farke would not comment on reports linking Norwich with a move for 19-year-old midfielder Adam Phillips, who was released by Liverpool at the end of last season.