Newcastle United manager Matthias Jaissle says a decision about Bruno Guimaraes' future had already been taken by the time he first met the club's departing captain.

Arsenal are set to complete their protracted £75m move for the midfielder after a breakthrough in discussions.

Jaissle briefly spoke to Guimaraes at the club's training camp in Spain earlier this week, but the 28-year-old went on to bid an emotional farewell to his team-mates and club staff.

"I met him quickly, but the decision was already made," Jaissle said in his first meeting with reporters following his appointment as head coach.

"It was a nice conversation. He's a fantastic player and a great human being. It's tough but for him now it's the next challenge and we need to deal with it at a later stage.

"We trust the players who are here already, but we will also see some changes."

Guimaraes is set to become the fourth key player to leave Newcastle in less than a year.

Anthony Gordon and Sandro Tonali moved to Barcelona and Tottenham Hotspur respectively earlier in the window while Alexander Isak joined Liverpool last summer.

Club legend Alan Shearer has sent Jaissle his "very best wishes", but previously warned it could be a "tough season" with some "very challenging times ahead" in a column for BBC Sport.

Jaissle, though, sees the club's rebuild as an opportunity to start a new cycle and mould a young, hungry side after succeeding predecessor Eddie Howe.

"This is a challenge and there are so many transitions at the moment," he said. "Many big players left - legends of the club - but we need to see it as a chance.

"Not having too many excuses now, just thinking forward about what we can influence.

"Control the controllables, I used to say, and I'm sure there will be progress this season."

Jaissle has been focused on coaching the players currently at his disposal on the training pitches, but Newcastle are working on further additions before the start of the season.

Newcastle have shifted policy this summer, targeting younger players on the Continent, with Lukas Hornicek the club's oldest arrival by a reasonable distance at 24 years of age.

The club have spent around £146m to date on goalkeepers Hornicek and Ewen Jaouen, midfielders Aladji Bamba and Sean Steur and winger Bazoumana Toure.

The quintet, like Jaissle, have never experienced life in the Premier League before.

However, following trophy-laden spells in Saudi Arabia and Austria with Al-Ahli and RB Salzburg, the 38-year-old is relishing the challenge ahead.

"This is something I don't have on my CV, but that's normal in football," he said.

"At one point it has to be your first step and I'm now at that moment after being successful in Saudi Arabia and Austria.

"Everyone was dreaming about being a part of the Premier League and now here we are."

Newcastle start the new campaign against Liverpool at St James' Park on 23 August.