Martin O’Neill admitted Celtic were “well beaten” by Sporting CP but insists the 4-1 defeat provided a valuable pre-season test for his squad.
The Hoops ended their Portugal training camp with a heavy loss after Sporting pulled away late in the second half.
Camilo Duran had brought Celtic level with his first goal for the club, but three quick Sporting strikes turned the game and left O’Neill’s side with a difficult scoreline.
Despite that, the Celtic manager believes the match gave both his senior players and younger prospects exactly the type of challenge they needed at this stage of the summer.
Speaking to CelticPlayer, O’Neill said: “First of all, it was a fantastic workout for us in many ways.
“It was a really good workout. They pulled away from us towards the end, especially after the number of changes we made.
“Overall, though, I was delighted to get this game. Absolutely delighted.
“We were well beaten in the end, but it is pre-season and we are trying to get fit for the most important part of the campaign, which is the opening game.”
O’Neill felt Celtic’s younger players would benefit from facing opponents of Sporting’s quality, while he also identified areas where the full squad must improve.
He added: “First of all, it is a great experience for some of the young boys to play against a side like that.
“The senior players can learn from it as well. We can all learn from fundamental things such as closing players down, trying to get there first and recovering more quickly.”
The main positive on the night was Duran’s debut.
The summer signing came off the bench, pressed the Sporting defence into a mistake and finished to score Celtic’s equaliser.
O’Neill was pleased with the forward’s effort and compared his willingness to chase defenders with Daizen Maeda.
He said: “I was just delighted with him.
“I did not think he received a great deal of service towards the end, especially with the changes we made during the game.
“Overall, I think he will be a really good acquisition for us.
“We have spoken about Maeda being able to close players down. He might be the second Maeda in that respect.
“He certainly has a willingness to do it.”
Duran had only recently joined the squad and went into the match after missing a training session through illness.
His goal was an encouraging first step, even if the final result took much of the shine away from Celtic’s night.
O’Neill now wants to see progress when Celtic return home to face Middlesbrough at Parkhead.
He said: “Of course. That is the whole idea.
“We want to improve each time.
“We have the game against Middlesbrough, which will be another big test for us.”
The Sporting defeat exposed areas that still need work, but O’Neill’s focus remains on fitness, learning from mistakes and preparing Celtic for the first competitive match of the season.