However, Luis believes that the unbeaten Premier League leaders can take plenty of positives from their performance at the Theatre of Dreams.
"When they score a goal like that of course it's difficult, but they celebrated one point at their home ground so we have to be proud. We haven't lost yet, the team is improving all the time and we have to keep it up," he told the club's official website.
"We feel we could have won the game, we had a lot of chances to score and good combinations on the ball. In the last moment they had the set piece and scored, but that's football, these things can happen."
Chelsea return to action on Tuesday when they travel to Shrewsbury Town in the fourth round of the League Cup.