Ronald Koeman was left feeling positive for the future after Barcelona kicked off their pre-season campaign with a hard-fought 4-0 win over 10-man Gimnastic at the Estadi Johan Cruyff.

Albania striker Rey Manaj, who has never played a competitive game for Barca and is expected to move on this window, scored a second-half hat-trick in Wednesday's friendly in front of around 2,000 supporters.

Alex Collado netted the other goal for Barcelona, but the game was not as one-sided as the scoreline suggests as three of the four goals were scored in the final five minutes.

Koeman named a different line-up in each half, with the likes of Sergino Dest, Gerard Pique, Miralem Pjanic, Sergi Roberto, Riqui Puig and Samuel Umtiti starting the game.

New signing Yusuf Demir, brought in on an initial loan from Rapid Vienna and described as the 'Austrian Messi' for his playing style, also played his first 45 minutes for the Catalan giants.

The second half saw a far more inexperienced side fielded and contained just one player, goalscorer Collado, with a competitive appearance for Barca under his belt.

Manaj stole the show with his three goals, the pick of those an angled finish into the roof of the net as Gimnastic, who had Alex Quintanilla sent off in the first half, started to tire.

Without Lionel Messi as the superstar forward delays signing a new contract, as well as new signings Eric Garcia, Sergio Aguero and Memphis Depay, Koeman was pleased with what he saw.

"The important thing is that everyone has played 45 minutes; it is something important for the physical side of things," he told Barca TV. 

"We dominated and we got a good result. The game leaves positive feelings.

"My players have returned well. They also trained hard this morning – it's all about getting fit. With two different teams, everyone has had a chance to show their quality.

"It goes without saying that there are certain names that stood out."

Following a season played behind closed doors due to the coronavirus pandemic, Wednesday's game marked the first time Koeman has managed Barca in front of a home crowd.

"It was strange having people here, but thank goodness they were here," the Dutchman said. 

"I love that there is an audience and also the players do too. They helped us. We really needed it."

Barca have tougher tests to come than third-tier Gimnastic, with Girona up next on Saturday before facing Stuttgart and Salzburg in Germany and Austria respectively.

"On Saturday we will have more players available," Koeman added. "We have a little time now to train all together. 

"In Germany we will have good games, against high-level rivals, where we can draw good conclusions."