The Blues had already qualified for the last 16, but the midfielder took his chance in a strong lineup at Stamford Bridge to show what Graham Potter had been missing by not using him this season.
His whipped finish in the 30th minute at the edge of Zagreb’s box ultimately helped his side earn three points and a morale-boosting win after a dismal defeat to Brighton at the weekend.
However, he offered so much more than his goal in difficult circumstances, after becoming a curiosity due to his non-selection.
Most were projecting a possible tough debut like that of previous loan midfielder Saul Niguez, but the Switzerland international ignored the noise to dominate in west London.
His first moments on the ball came after a returning Kalidou Koulibaly played him into pressure inside his own half. Yet his touch and turn rescued the situation with players around him.
His great use of possession was evident throughout, completing 98 percent of his passes despite having not played a competitive match in over three months. He often drove through midfield, beating duelling players and winning three fouls.
Zakaria’s defensive actions were enormous, winning possession seven times. After netting with his only shot, he was hauled off in the 71st minute with a suspected knock, as he walked down the tunnel.
It didn’t look serious, though, and we will likely see the rangy defensive midfielder soon.
The conversation will rightly remain more around his good display and Standard Sport understands that Zakaria will remain at the club until the end of the season.
That’s because his debut means that he can’t move on loan to another club, with also Juventus unwilling to recall him.
The debate will now centre around whether Chelsea will trigger his £25million option to buy, which they agreed to along with the season-long loan.
It was heartwarming to see Zakaria change the conversation around him after Potter praised his positive influence behind the scenes despite his lack of minutes.
Zakaria took his chance and no one would begrudge him another appearance in a more important game, with matches against Arsenal, Manchester City and Newcastle coming up before the World Cup.