To follow a Pro Player:
1. Go to the "Explore" Menu
2. Tap "WTA Ranking" for women players / Tap "ATP Ranking" for men players
3. Select the player if he/she is Top 10, otherwise you can search for him/her by the first name and surname
4. As soon as you've found the player you wanted to follow, tap him/her
5. Tap "Subscribe"
6. The Players you're following will from now on appear directly in the "Explore" Menu through a personalized ranking
7. If you want to go back to the general ranking tap "See ranking"
For your information, the players you're following appear with a star (Picture below):
From now on the scores of the players you're following will appear on the "Feed" Menu.