Matthias Jaissle joined Newcastle United from Saudi Pro League side Al-Ahli. It was a night which ended with Newcastle United lifting a trophy, but there was certainly no danger of new head coach Matthias Jaissle getting carried away. Not after defeating Valencia in his first pre-season friendly in charge at the Mestalla Stadium.

"We will not smash the locker room now and celebrate," he said after the 2-1 win. "We still have a lot to do." That was quickly apparent after Newcastle fell behind inside four minutes, following Filip Ugrinic's curling opener. But Jaissle will have taken heart from his players' response in a feisty contest, not least after Anthony Elanga was stretchered off following a bad tackle from Jose Gaya, which earned the Spaniard a red card.

Although Jaissle readily admitted he was "in fear" after seeing Elanga in distress, the Newcastle forward was walking a little later and it is not thought to be a serious injury after he bruised his shin. Newcastle could have lost their heads, but striker Yoane Wissa came off the bench to score two goals, while fellow substitutes Bazoumana Toure and Sean Steur also caught the eye following their summer moves from Hoffenheim and Ajax respectively.

"Winning games always helps to gain confidence," Jaissle said. "We also knew that we had a hard week behind us. The players did well and there was a huge commitment to see in each session, so they really deserve two days off and then we start again."

There has been little time to waste following a period of dramatic change at the club. Former head coach Eddie Howe has moved on while key players Alexander Isak, Bruno Guimaraes, Sandro Tonali, and Anthony Gordon have all left in the last year.

Gallows humour gripped some supporters who made the trip after they adapted a chant which once featured the names of Guimaraes and Isak, who are now with Arsenal and Liverpool. "We've got someone in the middle," they sang. "He knows exactly what we need. [Sven] Botman at the back, someone in attack, Newcastle are going to win the Premier League."

But it is not hard to imagine those blanks being filled in as a new generation steps up. The average age of the squad has been dramatically lowered and, on Saturday, forward Harvey Barnes was the oldest starter at the age of 28. It felt like a potential sign of things to come as goalkeeper Lukas Hornicek, 24, midfielder Aladji Bamba, 20 and forward Toure, 20, made their debuts while 18-year-old Steur impressed from the bench.

Jaissle has a history of developing young players at RB Salzburg, which was a big draw for Newcastle, and he knows better than most what they need. "Time is the key," Jaissle said. "They're young lads. It's never going to be easy in football, especially at the highest level, but we're here to do that."

Malick Thiaw was among the elder statesmen as he led Newcastle out as captain on his 25th birthday and this side will certainly need youthful vigour to play Jaissle's intense brand of football. Jaissle was a vocal presence throughout on Saturday, urging the visitors up the field, and rarely stood within the markings of his technical area.

He was even running down the touchline in tandem with his players as they advanced on goal at times. Just as there is a fine balance to strike on the field, so, too is there one off it. Newcastle are in the market for additional experience, particularly in the middle of the park, and veterans Dan Burn and Fabian Schar will remain important voices in the dressing room.

But Jaissle has also shown the first sign of a ruthless streak. Nick Pope was a pivotal figure under his predecessor, but the German left the 34-year-old out of the squad altogether against Valencia. "I had a talk with Nick," Jaissle said. "I really appreciate what he did in his career so far. He knows exactly the situation right now and we need to deal with it in the best possible way, but I always appreciate the player and the human being behind."

It has been a whirlwind first week in Spain and Jaissle now returns to Newcastle for the first time as the club's head coach. The 38-year-old already has a landmark in mind to see before he is formally unveiled at St James' Park next week. "For sure I will be visiting the stadium and getting my first impressions," he said.