The pop star was pictured having an intense session at David's newly opened gym on Sunday (23 February) and appeared to be put through his paces, as he went head to head with the former WBA heavyweight champion.
Donning his boxing gloves, Tinie tried his best to keep a serious face while jabbing at David and receiving some expert advice on his fighting technique.
Although the 33-year-old boxer isn't afraid to take off his top and display his impressive six-pack, he chose to cover up this time (boo!) and wore a baggy black T-shirt and red shorts.
Other members at the gym were spotted in T-shirts branded with the Hayemaker Gym logo, whereas Tinie opted for all-black to match his gloves.
The 'Written In The Stars' rapper posted a photo of himself and David on his Instagram page, proving to his fans that he takes no days off when it comes to staying in shape.
Tinie wrote: "Tinie Tempah Vs David Haye at the Hayemaker training camp w/ @mrdavidhaye & @RTfitness #HAYEMAKERTRAININGCAMP #YESEVENONASUNDAY #SUNDAYFUNDAY."
We're not sure it's such a "funday" when you swap a lie-in for a few rounds with a former boxing champ!
Nevertheless, David was impressed with the chart-topper and wrote on Instagram afterwards: "@tiniegram came down to the Hayemaker Gym and put in overtime!! Great work ethic in the gym."
As long as he didn't "pass out"!
Last week seemed to be a pretty busy one for Tinie, as he was spotted on the FROW at London Fashion Week with good pal Harry Styles and attending the Elle Style Awards in a shiny red suit.
And the weekend before was also a start-studded one for Tinie, since he rubbed shoulders with Brad Pitt and Angelina Jolie and high-fived Prince William.
Does he ever take a day off?!
Watch Tinie's music video for 'Pass Out' below.
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