Sturridge has played no part in pre-season after suffering an injury in England's 1-1 draw with the Republic of Ireland back in May.
The England international is now back in training and Downing has been quick to praise the forward following his return.
"Daniel has looked really sharp and it's great to see him back training again," Downing told the Liverpool Echo.
"Hopefully he can get some minutes against Celtic and then be ready for the Stoke game. It's a big plus for us to have him back fit before the start of the season. He settled in very quickly [since signing in January] and I think he really enjoyed playing every week after being on the fringes down at Chelsea.
"He's got great ability, pace and strength. He causes defenders a lot of problems and if he carries on where he left off last season we'll be delighted."
Sturridge signed for a fee of around £12m in the January transfer window.