But Chelsea avoided elimination from a second cup competition in a week as Batshuayi’s first-half double and a brilliant Marcos Alonso free-kick ensured progression to Monday’s fifth-round draw.

A second win from eight games this month, not including the third-round penalty shootout victory over Norwich, eased talk of crisis, on the field at least.

Antonio Conte has insisted he is happy at Chelsea, but did little to diffuse talk of friction with the club hierarchy.

Chelsea supporters sang their support for the Italian here; the visiting fans did likewise for Rafael Benitez.

Benitez knows all about turmoil at Chelsea. He secured Champions League qualification and the 2013 Europa League during a seven-month interim spell, but the affection of many Blues fans was lacking.

Batshuayi scored the goal which delivered the Premier League title in Conte’s first season in charge.

The Belgium striker now has 10 goals this season. Not a bad record, particularly when you consider 14 of his 25 appearances have come off the substitutes’ bench, many in the dying embers of games.

The frustration with Batshuayi centres on his poor hold-up play. Too often he relinquishes possession when an outlet is needed.

And he could be allowed to leave before Wednesday’s transfer deadline, particularly if a rumoured deal for Roma’s Edin Dzeko materialises.

David Luiz is out of favour at present and his future has been the subject of speculation, but his absence here was attributed to an ankle knock in training.

Chelsea struggled to hold on to the ball in the first half and might have gifted a goal to Newcastle.

But Dwight Gayle’s indecision reprieved Davide Zappacosta after the Italian’s poor pass was intercepted. Willy Caballero then saved a Jonjo Shelvey volley.

Chelsea had half-chances, but their accuracy in the final third was perhaps best summed up by a Danny Drinkwater shot which went out for a throw in.

That changed when Antonio Rudiger fed Pedro down the right and the Spaniard threaded a cross-field pass 40 yards to Eden Hazard, turning the Magpies defence.

Hazard waited and teed-up the on-rushing Alonso, who had the presence of mind to play the ball on for Batshuayi to tuck in. There may have been a suspicion of offside, but without the Video Assistant Referee, there was no review and the goal stood.

Rudiger curled a left-footed shot from 25 yards around the far post before Chelsea, and Batshuayi, enjoyed further good fortune.

Pedro and Hazard combined to find the striker, whose shot ballooned up off the leg of Jamaal Lascelles and in.

Caballero saved from Shelvey and Chancel Mbemba in quick succession before Chelsea resumed on the attack.

Pedro fired just over and Alonso had a volley saved by Karl Darlow.

Alonso had his seventh goal of the season when he curled in a 25-yard free-kick after Zappacosta was fouled.

Darlow denied Batshuayi in stoppage time as the Blues eased into the next round.