Changes are coming to the Grand Slam Track event in Philadelphia.

Founder and commissioner Michael Johnson announced on Thursday that the original three-day schedule for the professional track league event will be condensed to two days of competition.

The Philadelphia Slam will now begin on Saturday, May 31 and wrap up on Sunday, June 1 at Franklin Field.

"Coming off an amazing sold-out Miami Slam, we've taken time to celebrate the successes we've achieved in our inaugural season, but also have looked for ways to improve Grand Slam Track in real time," Johnson said in a release.

"We've said all along we want to listen to our fans, athletes, and coaches, and having heard feedback from various key stakeholders, we've made the decision to condense our schedule in Philadelphia into two, high-octane, and intense days of combat racing. We want to be the most flexible, adaptive, and fan-first league in sports, and we believe making these changes will improve the Grand Slam Track experience for all."

The move to a two-day event results in a significant change to the long distance category. The three-day competition window had allowed for a day of rest for the athletes between their 3,000-metre and 5,000m events, but now they will compete in a single 3,000m race in Philadelphia.

That change also comes with an altered prize pool for long distance athletes, with winners taking home $50,000 US instead of the $100,000 previously up for grabs.

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The final stop of the Grand Slam Track season is in Los Angeles from June 27-29.

All Grand Slam Track events will be streamed live on CBCSports.ca and on CBC Gem. For a full broadcast schedule of athletics events this season, click here.