Jose Mourinho 's Chelsea  side put in an excellent display in the second half of their match against Southampton yesterday to earn a hard-fought three points and continue their pressure on Manchester City and Arsenal at the top of the Premier League  table.
Mourinho handed Spanish international Juan Mata a rare start but only gave him 53 minutes to influence the game before replacing him with Oscar. Oscar's Brazilian teammate Willian also replaced Andre Schurrle in the 53rd minute in a double substitution that proved brilliant for Mourinho. The two Brazilians sparked life into Chelsea and scored two goals of their own after Fernando Torres opened the scoring for the Blues.
Mata was clearly put off when his number was put on the substitutes board and Jose Mourinho was sure to address that look of frustration after the match when being interviewed by the press.
"The squad was brilliant in the way they answered to our needs. This match was particularly difficult because you need to work a lot to play against Southampton. To press them high you have to work a lot," Mourinho said.
"I think Mata's frustration was because of the result. We knew we had to win, if we didn't win this game, the difference to the leaders is bigger and when he came out, the team is losing two points.
"I think his frustration is about that. Because at the end of the game, everybody including him was happy in the dressing room and everybody was celebrating the victory.
"So for me, I have to believe that the frustration was because of the result. Oscar and Willian, they changed the game."
With the World Cup right around the corner now, Mata will be desperate to get some regular playing time under his belt to impress his national team manager Vicente del Bosque. Rumors of the Spanish international leaving Chelsea have been tossed around since the start of the season but it looks as if Mata could leave West London as soon as this month, with Mourinho opening the door to his departure in his most recent comments.