"[By handing Rafa Benitez] the finance to strengthen, we can go from a good team to a great team," Gerrard writes in the paperback update of his autobiography out next week, reports the Daily Telegraph.
The 27-year-old also hailed Benitez as an "outstanding" manager, although he admitted he was surprised by some of his tactical decisions in the 2-1 Champions League final defeat to AC Milan in Athens - not least leaving it late to bring on striker Peter Crouch.
"Rafa came up with the right game-plan in Athens," said Gerrard, referring to the manager's decision to swamp Milan's midfield with a 4-5-1 formation.
"In the second half (with Liverpool losing 1-0), I expected some subs sharpish.
"I trust Rafa. The manager clearly had belief in the players who were on, but I was surprised Crouchy did not come on earlier. Not just Crouchy, any sub. We needed something different."