Chelsea narrowly avoided a monumental FA Cup upset on Saturday evening, requiring extra time to eventually see off a spirited Wrexham side 4-2. The Blues were made to sweat by the Welsh outfit, who twice took the lead in a pulsating encounter that saw the hosts reduced to 10 men before two late strikes finally settled the contest in favour of the Premier League giants.Garnacho, who proved to be the difference-maker for the visitors, was full of praise for the opposition following the final whistle. Speaking to BBC One after the match, Garnacho said: "Incredible win. I think it was one of the hardest games of the season so far. We are proud, and we are in the next round. I think it was a great goal and a great pass from Dário [Essugo]. I am really happy. These games are different. You have to fight and the opposition played really good."The hosts started brightly and took a shock lead through Smith, before an Arthur Okonkwo own goal drew Chelsea level. Wrexham were undeterred, however, as Callum Doyle restored their advantage with a clever finish. Speaking on his goal, Doyle told BBC Sport: "Happened so fast. Josh [Windass] is fuming that I took it. It was just a little flick and it paid off!"Despite their heroics, the momentum shifted when Wrexham were reduced to 10 men following George Dobson's dismissal. Chelsea capitalised through Josh Acheampong to force extra time, where the numerical advantage eventually told. Former England striker Alan Shearer noted on BBC One: "That was hard for Chelsea. Cup competitions are about getting through to the next round, even if you haven't played well. This Wrexham team have pushed them all the way and they have given them an incredibly tough night."In the added period, it was the quality of Chelsea’s attacking options that ultimately told. Joao Pedro and Garnacho found the net to break Wrexham hearts and ensure passage to the next round. Shearer was particularly impressed with the impact of the Brazilian forward, adding: "Joao Pedro has made a huge difference for this Chelsea team with his composure and his ability to run with the ball. He has options either side of him, but he chooses to go on his own. Chelsea are through to the next round."The result was perhaps harsh on Wrexham, who were inches away from a late 3-3 equaliser through Lewis Brunt, only for the effort to be ruled out for offside. Even after the red card, the home side continued to threaten, proving they were more than a match for their higher-tier opponents for large periods of the night.Add GOAL.com as a preferred source on Google to see more of our reportingWhile Chelsea celebrate progression, Wrexham defender Doyle was left to reflect on what might have been. "It is a tough one to take against a top side. I thought we did really well until the last part of the game. The sending off didn't help us. It is a big test, and they're a big side in the big leagues, and it is a good test for us against top players. We have another game on Tuesday, so we have to keep going," he said. When asked about his club's promotion ambitions, he added: "Hopefully, that is the target, but we have just got to stick at it."The Blues will now wait to discover their opponents in the next stage of the competition, though questions will likely be asked about their performance.