Liverpool spent a reported club-record £36.7m fee on the Egypt international earlier this month after protracted negotiations with Serie A giants AS Roma.
Sarah scored 15 times and made 11 assists in Serie A last season as the African forward continues to develop into an exciting player despite a disappointing spell at Chelsea.
Manchester United boss Jose Mourinho has been heavily linked with a move to sign Croatia international Perisic but the Red Devils have struggled to reach an agreement with Inter Milan.
The 28-year-old winger only managed to find the net 11 times and created five goals for his team-mates as the Croatian had a less productive Serie A campaign than Salah.
Speaking to ESPN FC on Monday about whether Perisic would be a better signing for Manchester United than Salah at Liverpool, former Arsenal striker Robson said:
“He fits the bill better at Liverpool than Perisic does at Manchester United.
“I can certainly see Salah doing better at Liverpool. I think he will do well.”
Liverpool finished in fourth place in the Premier League in their first full season under Jurgen Klopp.
Manchester United ended up in sixth spot but won the EFL Cup and the Europa League crowns.
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