Three days after Chelsea displayed their rampant attacking potential to book a place in a Wembley final the reality that they remain a work very much in progress under Mauricio Pochettino was laid bare as they survived a late onslaught to secure an FA Cup replay against Aston Villa. One mitigating factor for their lack of potency was the fact Chelsea had only 72 hours preparation after dismantling Middlesbrough 6-1 to reach the Carabao Cup final while Villa had not been in action since 14 January. Villa’s goalkeeper Emiliano Martínez acknowledged the contrast in buildup after a man-of-the-match performance which enabled Unai Emery’s side to keep a third consecutive clean sheet in all competitions. “We had a week off, and then you draw Chelsea away,” he said. “We knew it was going to be tough but we had 6,000 supporters and we want to go on a Cup run. “They had chances and started the game really bright. They didn’t score and then I think we had really, really good chances to win the game.” Chelsea have been in imperious form at Stamford Bridge, with Pochettino’s side unbeaten in their last nine matches at home in all competitions. The Blues have also won their last eight home games in the FA Cup but Villa thought they had ripped up the form book to take the lead in the 12th minute. A well-crafted set piece led to Moussa Diaby’s long-range strike deflecting off youngster Alfie Gilchrist into the path of Douglas Luiz, with the Brazilian tapping into an empty net. VAR adjudged Douglas Luiz to have used his hand, and the referee, Robert Jones, had no choice but to disallow the goal. The 6,000 away supporters made their opinions known but were immediately drowned out by cheers of relief from the home fans. The fast-paced nature of the game continued minutes later, with Martínez called upon to brilliantly save Noni Madueke’s rasping shot. Moments later the Argentinian spared the blushes of his teammate Clément Lenglet when he denied Cole Palmer from point-blank range. A lack of cutting edge prevented Chelsea from making their dominance pay, Pochettino’s side unable to take any of their chances despite controlling proceedings. He recognised the issue but was adamant his young group is continuing to evolve. “They [Villa] have amazing players in attack,” Pochettino said. “They didn’t score and we kept a clean sheet. We face a team like Aston Villa, it is difficult. Of course, we didn’t score but we created chances. I trust and believe in my players, for sure, playing in this way that we are going to score.” Pochettino can point to the fact that Chelsea have already passed their goal tally from last season in half as many games to back up his belief but this match was one of few chances. When a rare opportunity was carved out, neither side was able to take advantage. In the 67th minute Cole Palmer squandered a fine opening to break the deadlock after Martínez’s poor clearance hit him on the back, but he completely mis-hit his shot and it trickled back to the relieved Villa goalkeeper. Djordje Petrovic then palmed the ball away well from an Ollie Watkins strike 74 minutes in, before the Serb superbly kept out Matty Cash’s fierce left-foot effort as Emery’s men cranked up the pressure. It was not enough, as Chelsea ground out the last 15 minutes to secure a replay.