Tottenham's fortunate start against Villarreal

Tottenham secured a 1-0 victory over Villarreal at home, but the win was anything but convincing.

The only goal came in the 4th minute from a calamitous own goal by Villarreal's goalkeeper, Luiz Junior, who fumbled a low cross from Spurs' Lucas Bergvall into his own net.

Despite the early gift, Spurs struggled to build on their lead. The match was "scrappy" and low on quality, with Tottenham failing to register a single shot on target for the rest of the game.

Villarreal, meanwhile, came close on a few occasions, notably from former Arsenal player Nicolas Pepe, but were unable to find an equalizer.

Spurs held on for a narrow win and a clean sheet in what was a nervy start to their Champions League return under manager Thomas Frank.

"I [have] definitely learned you have to be happy with your wins and appreciate them," Frank said to Amazon Prime Video.

"I think there were many good things. We defended really well and gave little away throughout the game against a really good Villarreal side."

Arsenal's super-sub victory at Athletic Bilbao

Arsenal, playing away at Athletic Club in Bilbao, had to work for their 2-0 win. After a tight and cagey first half, manager Mikel Arteta's tactical substitutions proved to be the difference-maker.

Gabriel Martinelli and Leandro Trossard were introduced, and they had an immediate and decisive impact. Within 36 seconds of coming on, Martinelli latched onto a pass from Trossard, burst through on goal, and slotted the ball past the keeper to break the deadlock in the 72nd minute.

The roles were then reversed late in the game, with Martinelli setting up Trossard for a deflected strike that sealed the victory.

"Something that we always discuss is that the finishers have to impact the game, and Gabi and Leo came on to make the difference for the team," said Arteta post-match.

"They was outstanding and the rest of the team as well. In many moments, they were at a very good level.

"When someone is able to win the game in those actions and be so clinical, it's exactly what we need because the threat can come from different ways and different players. I'm very pleased with that."

The Gunners' win was a testament to their squad depth, as the two substitutes turned a frustrating match into a comfortable victory.

Champions League: Arsenal, Tottenham off to winning starts in Europe