Purchase tickets and join the crowds at a game at Obafemi Awolowo Stadium. If there's nothing scheduled while you're in the area, you might like to check if the stadium offers a guided tour of the grounds.
You'll be spoiled for sightseeing choice when spending time in Ibadan. Obafemi Awolowo Stadium is an ideal place to begin here, but there are many other worthwhile attractions to check out. University of Ibadan, The Jericho Mall, and The Ventura Mall are close to the sporting facility and and will cap off your day nicely.