Jannik Sinner is not known as one of the most expressive characters on the tennis scene.
Even so, the Italian world number one's more subdued demeanour was glaringly obvious during his march to the US Open title.
Reserved celebrations, and increased mindfulness, were the result of Sinner being embroiled in a doping controversy which shook the tennis world to the core.
In the week leading up to the final Grand Slam tournament of the season in New York, it was revealed Sinner had twice failed anti-doping tests earlier this year.
Sinner, 23, was found to have low levels of clostebol - a banned anabolic steriod - but was cleared of fault or negligence by an independent tribunal.