Though canines love tennis for its bouncy yellow balls, humans appreciate the freedom to bark loudly with each swing and bury their favorite rackets all over the court. Become a tennis beast with today's Groupon: for $20, you get $40 worth of merchandise and services at Tennis ltd in Upper Arlington.

Enabling central Ohio's full-court frenzy for tennis for nearly 30 years, Tennis ltd stocks a robust supply of equipment, apparel, and accessories and provides professional repair service and recommendations. Seasoned volleyers can take advantage of the shop's demo program to test out Prince's EXO3 Tour 100 racket ($189), ideal for whacking ProPenn tennis balls ($3.19 per can) and pressing neat grid lines into fresh-baked sheets of Play-Doh. Gird your ankles with a pair of K-Swiss Tubes 100 running shoes ($74.99), or protect your pupils from the blinding rays of the sun and the equally blinding laser pointers of opponents with a pair of Tifosi sunglasses ($39.95–$69.95).

Tennis ltd's repair services salve wounded swatters suffering from an array of afflictions. Restringing ($24–$32 for synthetic string; $59 for natural) can often be done in less than 24 hours and, like the most popular kitten hotels, allows patrons to choose from 50 different varieties of string. Re-gripping ($10.99), bumper-guard replacement ($15), and other services keep rackets ready for whatever spheroids come bouncing their way.