Despite a valiant effort from Preston North End in the first half, four goals in the second saw Chelsea progress to the fourth round of the Emirates FA Cup.
PNE were more than a match for their Premier League counterparts in the first 45 and on another day may have led at half-time.
It was, however, level and the hosts took the game away from Ryan Lowe’s men in the second half through Armando Broja, Thiago Silva, Raheem Sterling and Enzo Fernández.
Right from the off, PNE – backed by almost 6,000 noisy fans – were in Chelsea’s faces and put their defence under real pressure as the hosts looked to play out from the back, while North End also experienced positive breaks through Brad Potts and Liam Millar on either flank.
Chelsea had the first meaningful chance of the game when Alfie Gilchrist’s cutback found Sterling, who saw his effort blocked at close quarters by Liam Lindsay.
At the other end a minute later, headers won in the air by Potts and Milutin Osmajić saw the ball break the way of Will Keane, and the forward chested and volleyed at goal, but goalkeeper Djordje Petrović was equal to it.
Freddie Woodman was called into action a few moments later to tip Sterling’s effort over, before he breathed a sigh of relief when Cole Palmer somehow missed the target from six yards, after he’d brought the ball down with only the ‘keeper to beat.
Potts again won his aerial duel in the 27th minute when he flicked on for Osmajić to break into the area, and the Montenegrin saw his shot across goal kept out.
PNE continued to look dangerous throughout the first period and created another opening in the 38th minute when two more headers were won in the air, but Keane couldn’t quite connect with his volley inside the area.
After the break, skipper Alan Browne curled just over the bar from 20 yards, before Axel Disasi fired over at the other end soon after.
Chelsea started to see more of the ball and broke the deadlock in the 58th minute when Malo Gusto’s cross from the left was flicked in by Broja.
The forward could have doubled his lead on the hour mark when he met Mykhailo Mudryk’s header from a similar range, but this time it clipped the crossbar on its way over.
Substitute Silva did get Chelsea’s second, though, in the 66th minute as he headed beyond Woodman from a Palmer corner.
That lead was soon three as Sterling sent a brilliant 20-yard free-kick over the wall and into the top corner.
Broja would have made it four shortly after if it wasn’t for a great defensive block from Hughes, after the forward had rounded Woodman and tried to find what looked like an empty net.
North End had a half-chance to get themselves on the scoresheet with a quarter of an hour left, however Lindsay couldn’t quite connect as he swung for an effort in the aftermath of a corner.
Chelsea rounded off the scoring in the 85th minute when the ball broke kindly for Fernández in front of goal and he tapped home. Despite initially being flagged offside, a lengthy VAR check saw the decision overturned and the tie ended 4-0.
Chelsea line-up: Petrović; Gilchrist (Silva, 61), Disasi, Colwill, Gusto; Caicedo, Fernández (Golding, 89); Sterling, Palmer (Gallagher, 76), Mudryk (Madueke, 61); Broja (Deivid, 76). Subs not used: Bettinelli, Bergström, Maatsen, Williams.
PNE line-up: Woodman; Storey, Lindsay, Hughes (Best, 74); Potts, Browne, Whiteman (Holmes, 87), McCann (Ledson, 88), Millar; Osmajić (Riis, 64), Keane (Evans, 64). Subs not used: Cornell, Cunningham, Frøkjær, Woodburn.
Attendance: 39,705 (5,961 PNE fans)
Referee: Mr T Bramall.