The Blues made a near-perfect start after Manchester City lost at Burnley on Saturday thanks to Diego Costa’s first Premier League goal in almost two months.
It’s positive rather than negative
However, Nemanja Matic conceded a penalty later in the first half and Dusan Tadic placed his finish past Chelsea goalkeeper Thibaut Courtois.
Loic Remy and John Terry were denied by some desperate Southampton defending in added time, and Mourinho felt his side were unfortunate to be denied a winner.
“Yesterday we had five points more than second, now we have six points more and one fewer match to play,” Mourinho told BBC Sport following his side’s draw.
“It makes our situation better than before the game. It’s positive rather than negative.
“The performance until the penalty, the team was stable and was playing, not amazingly well, but with control. Towards the end of the first half we lost control.”
Mourinho added: “When Ramires came on he stopped the counter attack. We created lots of chances in the second half to win the game. We were unlucky we couldn’t score.”
Chelsea are six points clear at the top of the Premier League table after their stalemate with the Saints in west London.
The Blues, who won the League Cup last month, have played a game less than defending champions Manchester City and third-placed Arsenal.
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