Before Ritchie joined the club six years ago, he had spent three years with Howe at Bournemouth.
The pair forged a strong relationship on the South Coast during the club’s ascent to the Premier League – and that bond has been reinforced in the North East.
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Ritchie – who came off the bench in Monday’s 1-0 defeat to Mainz 05 in Austria – has a year left on his contract at St James’s Park. The 32-year-old had been given what had been labelled as a farewell appearance away to Burnley on the final day of last season ahead of an expected summer exit.
Asked about Ritchie’s brief appearance at Turf Moor, Howe said: "It wasn't farewell or intentional from my side.
“I think it's well documented my relationship with Matty, we go so far back, and the respect for him I have as a person. He's been incredible for me.”
While Ritchie has played less first-team football over the past few seasons, he’s still been a big influence in the dressing room.
Ritchie has made 188 appearances – and scored 24 goals – since joining Newcastle from Bournemouth in the summer of 2016 following the club’s relegation to the Championship.
The former Scotland international was a big influence on and off the pitch during Rafa Benitez’s time as manager.
Ritchie is “passionate” about playing for United, but his family didn’t join him on Tyneside. While Howe wants to keep Ritchie, he doesn’t want to keep him away from his family.
"Matty's own personal situation … he will have his own thoughts,” said Howe, who has made striker Dwight Gayle available for transfer. “Mine’s to try and keep him, but it's well documented that Matty has been a way from his family for a long period of time.
"He loves playing for Newcastle – and is very passionate about the club – but, I think, it’s unclear what direction we’ll take this year. But, from both sides, there’s a lot of respect."
Ritchie came close to rejoining Bournemouth during Steve Bruce’s time as United head coach. Ritchie had well-documented training ground “row" with Bruce early last year.