Barca prevailed thanks to Ousmane Dembele's first-half strike to open up a three-point lead at the top of the La Liga table after Real Madrid slipped up at Villareal.
The Blaugrana boss was delighted with his side's performance and believes it makes a big statement of their title credentials.
"I liked the first half an hour," he said of the win. "The game was under control. The goal came from creating a numerical advantage through the middle.
"These are three golden points. We knew how to suffer (after). It's important to have kept a clean sheet. Without playing that well, we got the three points. It was a tough game but a big win.
"It's not just three points, it's a huge morale boost. I am proud of the team. We have made a statement that we are candidates to win the league."
Barça almost came unstuck at the end but defender Ronald Araujo produced a fine goal-line clearance to keep out Antoine Griezmann.
"Araujo is an extraordinary defender, just like Balde, Kounde, Christensen..." Xavi said. "He's a leader."