The Reds are in eighth place in the Premier League table and nine points behind leaders Manchester City following eight games in the 2017-18 season so far.
Liverpool played out a goalless draw with title contenders Manchester United at Anfield last weekend as the Red Devils managed to frustrate Jurgen Klopp’s side.
The Merseyside outfit lost 5-0 to Manchester City in their only defeat in the 2017-18 campaign so far, while Liverpool have also drawn with Burnley, Manchester United and Newcastle United.
Liverpool signed four players in the summer transfer window as Klopp recruited AS Roma forward Mohamed Salah, Hull City left-back Andy Robertson, Chelsea striker Dominic Solanke and Arsenal midfielder Alex Oxlade-Chamberlain.
Former Manchester City defender Mills identified where Liverpool look short in comparison to their title rivals as Klopp looks to cement the Reds’ place in the top four.
“They’re recruitment hasn’t been brilliant,” Mills told BBC Radio 5 Live.
“They still need a number one goalkeeper, one or two dominant centre-halves, a really strong powerful midfield player and a centre-forward who can score 20 plus goals a season.
“They are still three or four players short to win the title. They are five or six players short to challenge for the Champions League.”
Klopp was appointed as Brendan Rodgers’ successor in October 2015 and was handed the unenviable task of guiding Liverpool to a first Premier League title.
Liverpool finished in second place in the Premier League table in 2002, 2009 and 2014.
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