As Oaklawn Park prepares to enter the heart of its winter-spring season, the Hot Springs, Ark., racetrack announced a third purse increase, effective March 16.Track officials said increases in handle on the live product, as well as the popularity of Instant Racing, fueled the purse hike. Claiming races will get a $500 boost, while maiden special weight and allowance races will go up by $1,000.Instant Racing, a sort of pari-mutuel video lottery terminal that uses recycled races, is available at Oaklawn and Southland Greyhound Park in West Memphis, Ark. Oaklawn went online with the devices a few years ago and has posted steady gains in handle since that time.On March 23, Oaklawn will hold the $100,000 Rebel Stakes for 3-year-olds. It's the final local prep for the Arkansas Derby. On-track attendance is up this year with less than a month to go in the live racing season.