Chelsea secured a place in the last 16 of the Champions League and eased the pressure on Jose Mourinho.
The Blues have struggled this season but they won 2-0 at Stamford Bridge to finish as Group G winners and Willian feels it is a sign of better things to come.
“Of course,” said the winger. “Now the confidence of the team will improve after this result. We played well and we deserved it. The last few games we have played well and we have to continue that.”
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Chelsea will face either Paris St-Germain, Juventus, PSV Eindhoven, Benfica, Roma or Gent in the next round. The draw takes place next Monday.
Defender Kurt Zouma said: “We wanted to finish first in the group so we are very happy. We have been playing well for a few weeks but this was one of the best performances of the season."
Next up for Chelsea is a trip to leaders Leicester in the Premier League on Monday.
“We need to focus on the Premier League now,” said Zouma. “It will be very difficult for us but we have to win. We did not play well against Bournemouth but we played very well against Porto. Let's keep going like that on Monday.”
