The former Southampton captain spent most of the 2017-18 Premier League campaign on the sidelines due to a serious knee problem.
Lallana was forced to watch Liverpool FC’s impressive Champions League run from afar as the Reds reached the final in Kiev.
The 30-year-old made his first appearance of the season in a 2-0 win at Crystal Palace as a late substitute.
Jurgen Klopp handed the England international his first Premier League start in the title race in a 1-0 win at Huddersfield Town in November.
However, Lallana has struggled to break into the Liverpool FC team and has been limited to just 202 minutes in the Premier League this term.
Former Liverpool FC defender Warnock believes Lallana could have a big role to play in the second half of the season as the Reds look to win a first Premier League title.
“I spoke to Adam Lallana recently, he has been having some issues with his diet, trying to find the best way to get fit. He feels he is at a good point,” Warnock told BBC Radio 5 Live.
“He is a big player. A couple of years ago he was Liverpool’s Player of the Year and England’s Player of the Year.
“If he can get a run of games together he can have a big impact in this title race.”
Lallana has also made two appearances in the Champions League – featuring home and away against Red Star Belgrade.
The Liverpool FC playmaker was a regular under Klopp in his first 18 months at the Anfield outfit.
However, Lallana has struggled with persistent injuries since the start of the 2017-18 season to limit his impact.
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