Chelsea are enjoying a good spell of form at the moment. Since the arrival of head coach Thomas Tuchel, the London side have won six of their last seven matches, with the most recent coming against Atletico Madrid in the Champions League.
This weekend they have a big match against Manchester United and will be going through their usual pre-match rituals.
According to the Sun, they players have a little trick before games: putting their boots in the microwave to heat them up.
The players do this to apparently make the boots more comfortable as the material they are made from softens with the heat, making them more flexible.
Someone from Chelsea explained the strange habit.
"Modern football boots seem to be pull-on types with much tighter fitting leather relying on a squeeze effect to stay on rather than the laces," the source told the Sun.
"So, when cold they can be quite tough, quite stiff and awkward to wear at least when they first go on.
"The players put their boots in the microwave for a minute or two and the timer pings when they are soft enough. It's actually a valuable addition to their equipment."