Mohamed Salah returned to training ahead of Liverpool's Champions League quarter-final second leg against Manchester City on Tuesday.
Klopp hoping to start Mane-Salah-Firmino trident
Liverpool head to the Etihad Stadium with a 3-0 advantage, Salah having opened the scoring and set up Sadio Mane for the third after Alex Oxlade-Chamberlain's second in the first encounter at Anfield.
The Egypt international, who has scored 38 goals in all competitions, was forced off in the second half with a groin injury and sat out the Merseyside derby draw against Everton as a result.
However, Salah appears to be closing in on a return, having participated in the group work out at Liverpool's Melwood training facility.
It's not 100% but it's looking positive
When asked on Monday whether the former Roma and Chelsea winger would be available for the clash at the Etihad Stadium, Klopp gave an optimistic response.
"We're not sure 100 per cent, he was with the athletic coach [on Sunday]," Klopp told a media conference.
"Rather yes than no, but we have to wait and see for the reaction."
Andrew Robertson and Alberto Moreno, both of whom missed the 0-0 draw against Everton due to injuries, were also in training.