Alex Neil will undergo a scan on the ankle injury that forced him off at Charlton Athletic - but boss Alex Neil admits it does not look good for the midfielder.
Pritchard appeared to twist his ankle in a heavy challenge 15 minutes from the end of the goalless draw, and he needed treatment on the pitch before he hobbled off with the help of the physios, with Elliot Embleton coming on to replace him.
Pritchard has been a key player for Sunderland this season and he is someone that Neil knows well, having signed him for Norwich in 2016.
Go here for all the latest Sunderland AFC news
"The biggest concern I have got is Alex Pritchard, who has been fundamental for me since I came here," said Neil.
"His injury doesn't look good at the moment.
"Alex looked as though he rolled his ankle.
"We'll have to have a scan on it but I've known Alex for a long time, I've worked with him before, and I asked him how he was and from what he said it doesn't sound good."
While Pritchard went off during the game, two more players missed out entirely due to injury problems with Jermain Defoe and Leon Dajaku both absent, although Neil did not seem to be overly concerned about the severity of their conditions.
He said: "Jermain missed out with an injury issue. It's only a slight issue, but unfortunately he wasn't OK to be involved today.
"As for Leon, it was another injury, just a niggle."
Neil was left frustrated after Sunderland dominated at Charlton but could not find a winning goal, insisting that they did not get what they deserved.
He said: "I think we deserved to win - everybody could see that.
"For the first 35-40 minutes of the first half we were completely dominant and had probably four or five really good opportunities to score, but didn't quite take them.
"At the start of the second half, we started quite brightly but then for 20 or 25 minutes it became a bit scrappy.
"We made some really aggressive substitutions at that point and the game became a bit more open, a bit more end-to-end, and we again had two or three really good moments where could have won.
"We created more chances today than we have done in the last two or three matches but it is frustrating because we scored in every one of those games, but not today.
"What we have done though is give ourselves a platform by keeping another clean sheet and looking solid defensively, which I thought we were for large parts.
"The performance in the first half was as good as we have played since I have been here."
Sunderland missed the target with a series of opportunities, and they were also foiled numerous times by goalkeeper Craig MacGillivray, and when Dennis Cirkin did beat the keeper he saw his shot cleared off the line.
"It's a combination of a couple of things," said Neil.
"We weren't as clinical as we have been before, and the goalkeeper has had a good game.
"I don't think it falls solely on us, and I don't think it falls solely on them - it's a combination of both.
"But if you were to say to me before the game that we would have as much of the game as we had, I'd have taken that because I'd have thought we would score at least two goals out of that.
"We didn't though, and that's the frustrating part.
"But I am a big believer that if you take care of performances, points will come, and unfortunately today we didn't get what we deserved."
For the latest Sunderland news direct to your inbox, go here to sign up to our free newsletter
