They finished nine points ahead of their closest challengers, Atletico Madrid, and a staggering 19 points clear of Real Madrid. Everything appeared rosy.
Yet the side fell short at the business end of the season in other competitions. A humiliating collapse against Liverpool at Anfield cost the side a place in the Champions League final, followed by a shock defeat to Valencia in the Copa del Rey final.
Now questions are being asked of this Barcelona side. They have not won the Champions League since 2015, failing to even make the final since then. So how do they take that difficult next step?
They have already signed Frenkie de Jong, while Neymar and Antoine Griezmann appear to be on their way as well, as the club look to rectify their mistakes from last season by spending big.
Under the radar, they are now linked with a move for Inter forward Lautaro Martinez. Here is why the striker could be the player to drive Barcelona forwards.
He Has Already Developed a Partnership With Lionel Messi
It is common knowledge that Lionel Messi runs the show at Barcelona and has done for over a decade. Therefore, if Martinez is to fit in, he needs to be able to work alongside the five-time Ballon dOr winner.
The Copa America was evidence that the two of them are on the same wavelength. Having been restricted to the bench in the first game of the tournament, a humbling defeat to Colombia, Martinez went on to start the following four matches, scoring twice to help Argentina into the semi-finals.
He showed that he belonged at that level, linking up effectively with Messi throughout. Barcelona fans can expect the same if they play together at club level in the coming years.
He Can Produce in the Big Games
Last season was Martinezs first in Europe. With Inter manager Luciano Spalletti opting for a lone striker throughout the campaign, Martinez was often left on the bench, playing second fiddle to Mauro Icardi for the first half of the campaign.
However, when Icardi was dropped after failing to sign a new contract, Martinez was handed his chance, and he took it.
Martinez scored winning goals against Napoli, AC Milan and Parma, which were to prove crucial as Inter clinched the final Champions League spot on the final day of the Serie A season.
An overall tally of six league goals in 2018/19 was a little underwhelming, but he showed promise, and his ability to find the net when it mattered most is a quality that will have caught the eye of the Spanish giants.
His Best Years Are Ahead of Him
Luis Suarez has lead the line for Barcelona for the last five seasons, netting over 20 league goals in four of them. Yet it is his record in Europe that is a concern.
Just five goals in his last three Champions League campaigns is a poor return. At the age of 32, it is time for Suarez to be pushed for his place in the side. Martinez could do just that.
With his 22nd birthday not until August, Martinez still has plenty of facets of his game to improve on. He has shown glimpses of his potential already, but is nowhere near his peak yet. Playing alongside Messi and co. would allow him to reach that level sooner, as he aims to become one of the best strikers in the world.