Liverpool's Mohamed Salah celebrates scoring their first goal during the match Premier League between Liverpool vs Watford at Anfield, Liverpool, December 14, 2019. Liverpool forward Mohamed Salah kept up his scoring streak against Watford with a brace as the Premier League leaders sealed a 2-0 victory over the bottom club at Anfield. Action Images via Reuters/Carl Recine

Liverpool's Mohamed Salah scores their first goal during the match Premier League between Liverpool vs Watford at Anfield, Liverpool, December 14, 2019. Action Images via Reuters/Carl Recine

Liverpool's Roberto Firmino shoots at goal during the match Premier League between Liverpool vs Watford at Anfield, Liverpool, December 14, 2019. REUTERS/Phil Noble

Liverpool's Alisson saves a shot from Watford's Gerard Deulofeu during the match Premier League between Liverpool vs Watford at Anfield, Liverpool, December 14, 2019. Action Images via Reuters/Carl Recine

Liverpool's Sadio Mane scores a goal that is later disallowed after a VAR review during the match Premier League between Liverpool vs Watford at Anfield, Liverpool, December 14, 2019. REUTERS/Phil Noble

Liverpool's Mohamed Salah celebrates scoring their second goal during the match Premier League between Liverpool vs Watford at Anfield, Liverpool, December 14, 2019. REUTERS/Phil Noble