"Brendan's signings have really strengthened the team," McManaman told the Liverpool Echo.
"Simon Mignolet has done really well, Mamadou Sakho has slotted in well at the back and to get Victor Moses on loan from Chelsea was a great piece of business.
"I love the way Brendan has got the team playing, and they've got the likes of Glen Johnson and Coutinho to come back into the team over the coming weeks. When everyone is back the manager has got real competition for places so it looks very promising."
Liverpool are currently second in the Premier League table.