The former Napoli boss took over the reins from compatriot Antonio Conte in the summer after Chelsea FC finished in fifth spot in the Premier League table.
The west London side won their opening five Premier League games to make a promising start to life under the controversial Italian coach.
Chelsea FC dropped their first points in the season following a 0-0 draw with West Ham United at the London Stadium last weekend.
The Blues eased to a 1-0 win over PAOK in their opening Europa League fixture in Greece to make a strong start to their European campaign.
Sarri is still waiting to win his first major trophy in management.
Former Arsenal star Merson believes Chelsea FC will want to win the Europa League and finish in the top four under Sarri this term.
“The top four and the Europa League,” Merson told Sky Sports. “Looking at the team of the first game in Europa League, he’ll give it a right go. He hasn’t won anything yet.”
Chelsea FC will welcome Premier League leaders Liverpool FC to Stamford Bridge in their next top-flight fixture on Saturday evening.
The Blues won the FA Cup last term thanks to a 1-0 win against Manchester United at Wembley last season.
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