LAWRENCE (AP) — Brandon Rush returned to Kansas to have his jersey retired this week, and it so happened that the ceremony coincided with the No. 3 Jayhawks clinching a share of their 13th straight Big 12 title.Afterward, the nine-year NBA veteran gave this year’s Kansas team a few parting words.“He talked to us,” freshman Josh Jackson said, “about how the hard part is just beginning.”That’s because conference championships have become the minimum requirement at Kansas, where an NCAA-leading 60 banners have been hung in Allen Fieldhouse. Rush was part of three in the midst of their current run, the only three seasons he played before turning pro.But when his career highlights streamed across the video boards hanging over the floor at halftime Wednesday night, the biggest cheers were not for games against rivals Missouri or Kansas State.