The Cherries were sunk 3-0 at White Hart Lane in the Barclays Premier League, where Harry Kane struck twice in the opening 15 minutes before Christian Eriksen concluded the scoring the second half.
"It was a very tough day at the office," admitted Francis.
"We worked hard all week on a game plan that we needed to stick to and we knew what to expect from them.
"We knew all about their strengths but the game plan kind of goes out the window when they score after 45 seconds.
"After that it felt like it could have been like the home game against them, especially once they scored again. But we had to make sure that it wasn't."
After going 2-0 down early on, the Cherries fought hard to re-establish a foothold in the game.
And although they put on a much-improved second half display, Francis admits that it was a case of too little too late.
"At times we put our authority on the game," continued the defender.
"In the second half we were a bit better and managed to get a bit of respect out of the game.
"But when you concede like that, against a team going for the title, it's always going to be an uphill battle.
"Now we've got two weeks to get together and analyse that before moving on into another big game against Man City."
Eddie Howe called on his players to learn from their 3-0 defeat against Tottenham Hotspur, which you can read here.