The Blues eased to the Premier League title in their first campaign under the management of Antonio Conte last term.
Chelsea FC finished seven points ahead of their closest challengers Tottenham Hotspur to win the title for the second time in three seasons.
However, the title holders have struggled to defend their title following the high-profile departures of Diego Costa and Nemanja Matic last summer.
Chelsea FC are in fifth place in the Premier League table and 28 points behind runaway leaders Manchester City with eight games to go.
The Blues are facing the real possibility of a season without Champions League football given Chelsea FC are 10 points adrift of Liverpool FC and Tottenham Hotspur.
However, Willian is confident that Chelsea FC can bounce back next season and reel in Manchester City to challenge for the 2018-19 Premier League title.
“Of course they continue to do very well this season,” Willian is quoted as saying by Metro. “Last season they did well as well. They have a great team. Great players. Quality players.
“But the Premier League is very difficult to say that one team is going to dominate the next few years. I don’t think so. Next season will be totally different to this season.
“Maybe they can win again but you never know because Chelsea are going to come back stronger for sure.
“You also have Liverpool, you have Tottenham, you have Manchester United, Arsenal — a lot of teams that can win the Premier League.”
Chelsea FC can still finish the season with silverware if the Blues beat Southampton to reach the FA Cup final against Manchester United or Tottenham Hotspur.
The Blues haven’t won the Champions League since 2012 when Chelsea FC beat Bayern Munich on penalties.
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