GRAHAM POTTER turned to his ultimate Z-lister to end the Champions League group stage on a high note.<br /><br />Denis Zakaria was finally allowed out on pitch for a memorable debut in which he scored the winner to clinch Chelsea’s comeback.<br /><br />However, Ben Chilwell's World Cup dream may be over after pulling up with a hamstring injury at the end of the game.<br /><br />The England international was clearly in some pain and had to be carried off by medical staff after the game.<br /><br />Switzerland midfielder Zakaria was signed on loan from Juventus on deadline day in the summer and has sat on his hands ever since.<br /><br />But in last night’s final Champions League group game and with Chelsea already assured of top spot, the forgotten man of Stamford Bridge received a long-awaited call up.<br /><br />It would be stretching a point to claim Zakaria turned in a match winning performance. But he popped up when needed to see off stubborn Zagreb with a scuffed goal after half an hour.<br /><br />The shot took a slight deflection off a defender on the way over the line but Chelsea boss Graham Potter won’t care.<br /><br />And it was the clear the goal meant a lot as he was mobbed by team-mates who ruffled his hair. <br /><br />When he hobbled off with 19 minutes to go, Zakaria was treated to a standing ovation from fans in the Stamford Bridge West Stand, acutely aware of how frustrated the player must have been in recent weeks.<br /><br />With a World Cup around the corner, any game time is precious to players now and Zakaria played his part in his side’s win last night.<br /><br />For a game with nothing to play for except pride and restoring confidence Potter went for it with his line up: A strong starting XI with the exception of forgotten man Zakaria.<br /><br />Clearly last night’s game was an exercise in running Saturday’s 4-1 pummelling at Brighton out of the system and yet another experiment with the formation from the new Tinkerman.<br /><br />A back four and a front two comprising Raheem Sterling and Pierre-Emerick Aubameyang, sandwiching a midfield diamond.<br /><br />And for a time it looked as if this latest reworking of the tactics was going to backfire like it did at the Amex Stadium at the weekend.<br /><br />Dinamo Zagreb took a shock lead in the eighth minute. The third time in the last four games Chelsea have gone behind.<br /><br />A right wing cross from right back Sadegh Moharrami dipped at the far post and cannoned back across the box off the back of Cesar Azpilicueta’s head.<br /><br />Zagreb striker Bruno Petkovic was in the clear to power home a header from six yards. <br /><br />Returning keeper Edouard Mendy had no hope of keeping it out and the defence which shipped four goals four days previously gifted the opposition another goal.<br /><br />Potter has never had such a quantity of quality players at his disposal in his managerial career. <br /><br />Maybe it is the embarrassment of riches that he finds confusing? Like a spoilt kid on Christmas Day who doesn’t know which expensive present to play with first.