The Blues boss watched on as his side scraped a 4-3 victory against the Black Cats, who scored two of their trio from corner situations.
It was a very good performance. Even defensively, I think we did well, but the set-pieces... In the last six minutes of extra time, if they had two more corners, they would have won 5-4.
When you play so well, you have to win comfortably and not give a headache to the manager in the last six minutes.
Mourinho will be extremely pleased to escape the Stadium of Light with three points. The topsy-turvy nature of the match kept his team on their toes throughout.
Eden Hazard's masterclass—which saw the Belgian talent produce two excellent goals and an assist—proved to be vital in a tie that highlighted the difficulty of consistently winning Premier League football matches.
Chelsea's returning manager lavished Hazard with praise, calling his display "the best" and outlining the 22-year-old's improved sense of ambition for the win:
The talent, we know, but the ambition from the first to the last minutes for me, it was the first time because he has a great talent, but sometimes he does incredible things and after that, he disappears from the game.
Will Chelsea win the Premier League this season?
Although there is work to be done from defensive situations—goals from Jozy Altidore, John O'Shea and Phil Bardsley confirming this point—Mourinho will take heart from his side once again overturning a deficit to claim the win. The victory takes their total to 11 points from losing positions, adding an extra three to OptaJoe's previous tweet.
A difficult test against Arsenal precedes this match, suggesting Mourinho's men will need a quick defensive improvement if they are to challenge Arsene Wenger's squad in the long run.