Papiss Cissé scored a breathtaking brace to damage Chelsea’s hopes of securing a fouth-place finish, with the Magpies’ 2-0 win leaving the Blues needing to beat Bayern Munich in the Champions League final to guarantee their place in next season’s competition.
“It’s going to be difficult now for us, we’re obviously behind,” Di Matteo told Chelsea’s website.
“The season has proven difficult but we will keep pushing and we won’t give up.
“We’ve lost many points during this season at many places, and looking back over the whole season that’s why we are in the position we are.”
Cissé handed the visitors a surprise lead in west London when he deftly controlled Davide Santon’s cross and unleashed a first-time shot past Petr Cech.
And 26-year-old netted his 13th league goal in just 12 appearances with a spectacular half-volley from 25 yards deep into stoppage time to seal a result which boosts Newcastle’s hopes of a top-four finish.
Chelsea’s interim boss Di Matteo conceded fatigue affected his players after a demanding run of games which has seen the Blues book their place in the Champions League showpiece and Saturday’s FA Cup final.
“In the first half we couldn’t raise our tempo to where we needed to be to dominate the game,” Di Matteo added.
“The second half was much better, we pushed Newcastle back into their half and created a few chances, had one cleared off the lines but Newcastle did well tonight. They defended well and scored two goals.
“We’ve been pushing the players very hard and they’ve responded extremely well.
“I selected a strong team to win the game it was our sixth game in 17 days. We can’t ask 10 players to go all the time, it doesn’t go like that.
“We have a good squad. They’ve given everything, the effort is there and we have asked them to push and push and push.
“We will regroup, pick them up and we have another big game on Saturday, and we’re going to go again. We look forward to the FA Cup Final, it’s a great event.”
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