The Egypt international had been stranded on 49 league goals for the club after failing to notch in any of his previous six league appearances, but his fine strike at St Mary’s saw him reach his half-century in just his 69th match – a Liverpool record.
Here, Press Association Sport looks at the seven fastest players to reach 50 league goals for the Reds.
Mohamed Salah (2019) – 69 matches
After a less successful spell at Chelsea between 2014 and 2016, Salah returned to the Premier League a year later from Roma and lit up his debut season on Merseyside with a record-breaking 32 Premier League goals in just 36 games.
The forward’s form has continued during his second campaign and he reached 50 goals for Liverpool with his 18th league strike of the season against Southampton.
However, his six-game goalless streak meant the Egyptian missed the chance to break Alan Shearer’s Premier League record to reach the 50-goal mark with a single club in the shortest amount of matches. The former England star took 66 matches to achieve the feat while at Blackburn.
Fernando Torres (2009) – 72 matches
The Spaniard was an instant hit following his arrival from Atletico Madrid in 2007. Less than two years later he brought up his 50th league goal with a 90th-minute strike against Aston Villa.
Torres went on to score 81 in 142 appearances in all competitions for the Reds.
Sam Raybould (1902) – 80 matches
Raybould was top-scorer with 17 when Liverpool won their first league title in 1901. He went on to become the club’s first player to score 100 goals, also the first to score 30 in a season, and finished with 129 goals in 226 appearances.
Albert Stubbins (1949) – 80 matches
Stubbins moved from Newcastle, where he scored 232 goals in 190 games in wartime, in September 1946 at the age of 27, scoring on his debut at Bolton.
He finished his first season with a league title and joint top-scorer with 24 goals. He eventually scored 83 in 178 games.
Roger Hunt (1961) – 81 matches
Five years before winning the World Cup with England – and three years after joining Liverpool – Hunt brought up his half-century. The same season he scored a remarkable 41 goals from 41 games as the Reds went up as runaway Division Two champions.
He finished with 286 goals in 492 appearances in all competitions.
Jack Parkinson (1909) – 83 matches
Given his debut in October 1903, Parkinson scored six times in his first 17 consecutive league matches but the following season netted 21 times in just 23 league and cup games.
In 1909-10 he reached the rare milestone of 30 First Division goals in a season as he brought up his half-century. He scored 129 in 220 matches in all competitions.
John Aldridge (1989) – 83 matches
Scored on his debut in February 1987 and the following season stuck nine goals in the first nine matches of the season, finishing with 26 league goals at the end of the campaign to set him well on his way to 50.
Finished with 63 goals in 108 appearances in all competitions.