Newcastle United manager Eddie Howe was unimpressed by the "really poor tackle" from Chelsea midfielder Moises Caicedo on Anthony Gordon that forced the attacker off through injury in Tuesday's EFL Cup quarter-final defeat at Stamford Bridge.

Caicedo received a yellow card just two minutes into the match for his late challenge on Gordon after he dragged his studs down the calf of the Magpies attacker.

Gordon managed to get through to half time and came out for the second half, but Newcastle's No.10 was unable to shake off the discomfort and was eventually withdrawn in the 52nd minute.

Emil Krafth was also taken off midway through the match following a late tackle from Levi Colwill, adding to Newcastle's growing list of absentees.

Speaking at his post-match press conference, as quoted by Sky Sports, Howe said: "Emil was too sore to continue – he's got a nasty gash on his shin which is quite sore at the moment.

"Anthony's the same. I thought it was a really poor tackle on him and the type of tackle you don't want to see taking one of our attacking players out of the game, and again he's very sore at the minute."

Asked whether Caicedo should have been sent off, Howe told Sky Sports: "I'm going on what other people's opinions are and not mine – I haven't seen it myself but people are telling me that they think it's a red card."

Sky Sports pundits Jamie Redknapp and Karen Carney disagreed over the decision made by on-field referee Jarred Gillett, who was unable to deliberate with VAR as the system is not used in the EFL Cup until the semi-final stage.

"It's a really stupid bad challenge," said Redknapp. "Two minutes into the game, it shouldn't matter what minute of the game it is, but I think it's a yellow. It's not a good challenge, make no mistake.

"What I can't understand is why you'd do something like that two minutes into the game. Look how far away from the ball he is, has he genuinely meant to hurt him? But it's such a stupid challenge."

Former Chelsea Women's midfielder Carney added: "That's a red for me. It's late. He's nowhere near the ball. He goes down the back of his calf and as the game goes on, you see their best player go off injured.

"I don't think he's meant to hurt him. I think it's just reckless from him, but at the end of the day that's gone down the back of my calf, I've had to go off and I'm thinking I'm hurt there.

"For me that's a red card, but we don't have VAR, the referee's let it move on, it's not a red in his mind and you move on – that's what the difference is."

Callum Wilson had put Newcastle in front in the first half before Mykhaylo Mudryk restored parity for Chelsea in the 92nd minute to force the tie to penalties, with the Blues prevailing 4-2 in the shootout after Kieran Trippier and Matt Ritchie were unable to convert from 12 yards.

Newcastle, last season's beaten finalists in the EFL Cup, will now turn their attention back the Premier League as they travel to Kenilworth Road to face Luton Town on Saturday.

While Gordon and Krafth have emerged as doubts for the clash with the Hatters, Alexander Isak (groin), Fabian Schar (glute) and Joelinton (hamstring) will also be assessed, while Nick Pope, Jacob Murphy (both shoulder), Elliot Anderson (back), Joe Willock (calf), Harvey Barnes (ankle), Matt Targett (thigh) and Javi Manquillo (groin) all remain sidelined.