Nottingham Forest goalkeeper Brice Samba had certainly done his homework before saving three Sheffield United penalties to send his team to the Championship Play-off final.
Samba had instructions on how each Blades player usually took their spot-kicks taped to his water bottle.
And that intel proved crucial as he kept out kicks from Ollie Norwood, Conor Hourihane and Morgan Gibbs-White to ensure Forest won the shoot-out 3-2 and made it to Wembley.
A picture of Samba's water bottle emerged on Twitter following Forest's win, with fans describing the Congolese keeper as a 'genius'.
Top of his list was Norwood and the instruction appears to say 'dive'. Samba duly dived to his right and punched away the kick to give Forest an early boost.
Brennan Johnson put Forest 1-0 up before Conor Hourihane stepped up for the Blades.
Samba's water bottle instructed him to 'stand' and that's what he did, sticking out a hand to divert the ball onto the crossbar.
After Cafu put Forest 2-0 ahead, Sander Berge stepped up for United's third penalty. As Advised, Samba dived but the wrong way as Berge pulled one back.
Steve Cook made it 3-1 to Forest before Iliman Ndiaye - not listed on Samba's bottle - scored.
There was then a moment of anxiety for Forest as Joe Lolley cleared the crossbar with their fourth kick.
But Samba then saved the decisive kick from Morgan Gibbs-White, diving low to his right, to seal it for Forest.
We can't see Samba's instruction for Gibbs-White on the bottle but whether he followed the instruction or used instinct, it was enough to send Forest to Wembley as they chase a top-flight return after 23 years.
The bottle list also featured instructions for Ben Osborn, Rhys Norrington-Davies, John Fleck, Daniel Jebbison and William Osula, who either didn't feature in the game or take a kick.
In an exchange on Twitter, Samba revealed that he wrapped the bottle inside his towel ahead of the shoot-out so nobody could dispose of it.
Forest went into Tuesday night's second leg with a 2-1 advantage from the first game at Bramall Lane. Johnson scored after 19 minutes to extend this lead.
However, the Blades fought back well in the second-half and goals from Gibbs-White and Fleck levelled up the aggregate score at 3-3, leading to a scoreless period of extra time and then penalties.
Samba said: 'I definitely enjoyed the shoot-out. I am happy to go to Wembley.'
He had earlier made a number of crucial saves to keep Forest in the game in the 120 minutes. They will now play Huddersfield Town for a place in the Premier League on May 29.
Instructions taped to water bottles or on a piece of paper tucked inside a sock have become commonplace crib sheets for keepers in games which might be decided on a penalty shoot-out.
Some confer with technical staff equipped with iPads on the touchline before the shoot-out begins.
Thousands of Forest fans poured onto the City Ground pitch following their win but the night was overshadowed when one fan headbutted Blades striker Billy Sharp, who was stood with his arms crossed in the technical area.
Sharp was left bleeding and required stitches, with police subsequently arresting a 31-year-old man on suspicion of assault.