The Blues suffered a disappointing 3-1 loss to their local rivals as they slumped to a damaging defeat in the race for Champions League qualification this season.
That result left the west London side in fifth place in the Premier League table and eight points behind fourth-placed Tottenham, facing an uphill struggle to try and break back into the top four this season.
It looks as if the Blues are going to have to settle for next season outside the Champions League spots as they look to try and end the season on a high by winning the FA Cup.
And Chelsea FC defender Alonso, who helped the Blues to win the title in style last term, believes that the west London side have been short of luck this term.
Speaking to Chelsea FC’s website after the game, Alonso said: “I think we aren’t having the same luck as last year.
“Also, other teams have improved and maybe we don’t have the consistency we had last year. I don’t think we played a bad game against Tottenham, we had many more chances than them.
“I think as in every game we just need to focus and concentrate for the 90 minutes because we were playing a good game, we were controlling, and then we conceded three goals. So it is hard to take.”
Chelsea FC will return to Premier League action on Sunday afternoon when they take on West Ham United in front of their home fans at Stamford Bridge.
The west London side are set to take on Southampton in the FA Cup semi-finals later this month.
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