Which scene is more worrying for Manchester United? The comical way they blew a two-goal lead in the final six minutes? Or the sight of both their first-choice center-backs being forced out of the game? 

It was certainly a roller coaster ride of emotions for the Red Devils faithful when they watched United's Europa League quarterfinal first leg showdown with Sevilla on Thursday night. The English giants looked to be coasting to a well-deserved victory at Old Trafford thanks to two smart goals from Marcel Sabitzer in the opening 20 minutes. 

However, the encounter took a drastic turn when Varane limped off at half-time before Martinez had to be carried off by his Argentinian compatriot Marcos Acuna and Gonzalo Montiel with what appeared to be a serious ankle injury.

Apprehension gradually crept into United's play, and Sevilla duly took advantage of the hosts' wobble to come back into the contest. First, Tyrell Malacia misjudged the bounce of a ball and diverted Jesus Navas' cross past goalkeeper David de Gea. Then, Youssef En-Nesyri's tame header deflected off Harry Maguire to wrong-foot De Gea again. 

The two late own goals have completely changed the complexion of the tie as United are left facing an uphill battle to clinch the semifinal berth they seemed to have sealed. Nevertheless, the loss of Varane and Martinez is a graver concern with the duo having been rocks at the heart of United's defense. 

When asked about the severity of the injuries, United manager Erik ten Hag said, "We've seen Licha Martinez drop out after a moment. There was no opponent involved so that doesn't look that great, so we're going to have to wait. I can't tell what it is, but it's not the Achilles area."

"He will not play on Sunday. It looks like that, but I can't say what is the diagnosis and I prefer to wait and then we are clear and we know exactly what it is. I have spoken with him and he is OK. He is calm." 

"I can't say at this moment and the same with Rapha [Varane]. I haven't spoken to Rapha after the game but it's an injury he's complained about over the past couple of weeks so we have to see how it is now." 

With top scorer Marcus Rashford still without a return date from his groin injury, United are plunging into an injury crisis at the worst possible time. To make matters worse, captain Bruno Fernandes will also not be available for the return leg in Spain next week after receiving a harsh handball booking.

With Luke Shaw, Scott McTominay, Alejandro Garnacho and Donny van de Beek already sidelined, Ten Hag is facing mounting selection problems for the crucial run-in of the campaign.  

But the Dutch tactician remained defiant. "Both [Sevilla] goals are really unlucky, two deflected. What can you do?" he mused. "Sometimes you have bad days and bad luck. Tonight was not our night."