Thomas Frank insists he had no idea he was drinking from an Arsenal-branded coffee cup in the build-up to Tottenham's defeat to Bournemouth, saying it would be "completely stupid" to knowingly do so.

Antoine Semenyo's 95th-minute goal guided Bournemouth to a 3-2 victory over Frank's misfiring team at the Vitality Stadium, leaving them 14th in the Premier League table.

Since the start of last season, only Wolves (36) have lost more Premier League games than Spurs' 30, with Frank barely improving on the form that saw them finish 17th under Ange Postecoglou last campaign.

And while Postecoglou brought the Europa League trophy to the Tottenham Hotspur Stadium, Frank got his hands on the wrong kind of cup on Wednesday.

Ahead of the game, images shared across social media showed Frank drinking from an espresso cup emblazoned with the badge of Spurs' arch-rivals Arsenal.

Those pictures attracted ridicule from rival fans, but Frank said the cups were simply left over following Bournemouth's game against the Gunners on Saturday and questioned why reporters would attach any importance to the incident. 

"They've been in the changing room the game before us. It's normal to say, 'give me a cup of espresso' before every game," Frank said.

"I definitely did not notice it. It would be completely stupid of me to take it if I knew.

"It's a little bit sad in football that I need to be asked about it. I would never do something that stupid.

"I think we're definitely going in the wrong direction if we need to worry about me having a cup with a logo of another club."

Frank will hope for a less eventful build-up on Saturday as Spurs host Aston Villa in the third round of the FA Cup, with West Ham their next Premier League opponents on January 17.