Ritchie was unhappy at being blamed for a failing to pass on tactical instructions to his team-mates after coming on in last weekend’s 1-1 draw against Wolverhampton Wanderers at St James’s Park.
The visiting team equalised soon after Ritchie’s second-half introduction, and Bruce, United's head coach, said: “The instructions didn't get on to the team quick enough on how we were doing it. When you look at the goal, we should have stopped the cross, and when the keeper (Martin Dubravka) looks at it, could he have done better?"
Ritchie and Bruce were involved in a confrontation at the club’s training ground on Tuesday.
And the Daily Mail has published details of the exchange between Bruce and the 31-year-old, who signed a new deal at the club last season.
Ritchie was a target for Bournemouth in January’s transfer window. Bruce revealed at the time that the winger was “frustrated” at a lack of first-team football at Newcastle.
Karl Darlow had been unhappy before the Wolves game after learning early in the week that he was set to be dropped through a newspaper report. Darlow was formally told that Martin Dubravka would start later in the week.
Bruce, under intense pressure at St James’s Park with the club just three points above the Premier League’s relegation zone, insisted that he had not lost the dressing room in January during a long winless run.
Newcastle declined to comment, though one source insisted that any issues between Bruce and Ritchie had been “resolved”.
The club is seeking to draw a line under the episode ahead of Sunday’s game against West Bromwich Albion at The Hawthorns.
Meanwhile, midfielder Jonjo Shelvey strongly defended Bruce in a podcast last week.
"He’s the best man manager I’ve worked under,” said Shelvey. “He knows how to speak to certain individuals. For me, as a footballer that’s what I want to work with.
"Steve Bruce is a Geordie. He’s stood on those terraces. He knows what’s expected. One thing he says is ‘if you’re not having a good game, you work your socks off’. He’s big on the stats side and how much we run. If you don’t run for him, you’re not playing the next week.”