Virtua Tennis 4

Obviously no quick fix to this.

Both ranked and player matches will contribute to your time.

If you have someone who also has the game you could play them as a player match and just keep rallying the ball to each other for aslong as possible as that will keep the time ticking up.

You will get this while aiming to get your rank A achievement.

But at same time as trying to win your game it will help towards this achievement to make the games last as long as you can.

If you'd like to know how much of the 10 hours you've played go to the main menu and click on 'My club' and then on overall stats page 6, in there it keeps all stats towards your achievements.