Crystal Palace forward Jean-Philippe Mateta was taken to hospital with a head injury after a collision with Millwall goalkeeper Liam Roberts early in their FA Cup fifth-round clash at Selhurst Park on Saturday.
Roberts was shown a red card, following a VAR review, after coming off his line to clear a long ball and catching the on-rushing Mateta in the head with his raised studs.
Frenchman Mateta, who has been in superb form for Premier League side Palace with 15 goals from 33 appearances, was given oxygen on the pitch during a lengthy stoppage before being taken off and put into an ambulance. He was replaced by Eddie Nketiah.
Speaking at halftime to the BBC, Palace chairman Steve Parish said Mateta had sustained a bad gash behind his ear and a head injury and was being assessed in hospital.
"Obviously, he's at the hospital, so we hope for the best. I mean there's a lot of emotion in football but we need to talk about that challenge. In all the time I've watched football, I've never seen a challenge like it.
"It is the most reckless challenge on a football pitch I think I've ever seen."
Palace were leading second-tier Millwall 2-1 at halftime.
The Indian Premier League match between Royal Challengers Bengaluru and Kolkata Knight Riders, which was to mark the tournament's resumption after the India-Pakistan ceasefire, was abandoned on Saturday due to rain without a ball being bowled.
Lewis Hamilton spoke of his devastation as Ferrari plunged to a qualifying low for the season on Saturday ahead of his first race in Italy with Formula One's oldest and most successful team.
Scottie Scheffler capped the third round of the PGA Championship in style to grab a three-shot lead over Sweden's Alex Noren on Saturday at Quail Hollow Club, where the world number one has a third major title in his grasp.
Crystal Palace's Eberechi Eze sparked a massive south London party by scoring the only goal to win the FA Cup 1-0 against Manchester City on Saturday and claim the club's first major trophy in their history.
The third round of the PGA Championship at Quail Hollow Club did not begin as scheduled on Saturday as play was suspended due to dangerous weather in the area moments before Masters champion Rory McIlroy was about to tee off.
The UAE has joined Arab states to demand an immediate halt to the war in Gaza and the establishment of a fund for its reconstruction during a summit in Baghdad.