Salah moved to Liverpool FC in a £39m deal from Serie A giants AS Roma in the 2017 summer transfer window.
The Egypt international struggled during an eight-month stint at Chelsea FC before his move to Fiorentina and AS Roma on loan.
Salah hit the ground running with a goal on his debut in a 3-3 draw with Watford on the opening day of the season.
The 25-year-old has since scored 29 times in 31 games in the Premier League in the current campaign
Salah is sitting at the top of the goal-scoring charts and five goals ahead of his closest rivals Tottenham Hotspur striker Harry Kane.
The African forward has netted eight times in the Champions League to help Liverpool FC reach the last 16.
However, former Arsenal defender Upson believes the Reds deserve credit for taking a punt on Salah.
“Unbelievable. People thought it was a lot of money,” Upson told Sky Sports. “Hats off to Liverpool for seeing what they saw.
“He has slotted into that team and into the philosophy of Jurgen Klopp perfectly.”
Liverpool FC finished in fourth place in the Premier League table last term to secure a return to the Champions League.
The Reds haven’t won the Champions League since 2005 when Liverpool FC beat AC Milan on penalties.
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