Chelsea's rocky season continues with upset loss to second-tier Middlesbrough in EFL Cup semifinals

Hayden Hackney scored the game's lone goal in Boro's 1-0 win as the Blues hope to turn it around in second leg

Chelsea's chaotic season hit another low on Tuesday when the Premier League side lost 1-0 to Championship team Middlesbrough in the first leg of the EFL Cup semifinals. Mauricio Pochettino started many of his first-choice players at the Riverside Stadium, which allowed the Blues to dominate the match in many aspects. They had 72% of possession and outshot Boro 18-6 but their efforts were moot since the hosts were the only team to actually find the back of the net.

Boro scored the game's lone goal in the 37th minute on a play that started with a throw in. After a little bit of build-up play, Isaiah Jones was able to make a dash down the right flank into the penalty area. From there, he played a quick pass to Hayden Hackney, who scored from close range.

Cole Palmer, Chelsea's standout so far this season, had an uncharacteristically poor day. He took four shots but failed to put three clear-cut chances away, though some of the credit goes to Boro goalkeeper Tom Glover. He made five saves on the night, making matters worse for the Blues on an already disappointing offensive day. Those five shots were the only shots on target Chelsea posted despite taking nearly 20 in total.

Chelsea still have a chance to climb out of this mess on Jan. 23 when they host Boro in the second leg of the semifinals. This might go down as perhaps the most notable loss in a season full of them, though.

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