I'm not a fan of tennis; however, I play Tennis Elbow 2013 all the time. Its PC only and there requirements aren't that strenuous. Don't let the year in the title fool you because the game is easily moddable and there are already tons of great mods available. Check it out at
http://www.managames.com/tennis/game_en.html. Game is also available on Steam (
http://store.steampowered.com/app/346470/). Mods can be found on the Mana Games website, specifically the Forums.
Oh, forgot to mention, there's a FREE demo!