Johnny Walker wasted no time picking his next target. Moments after stopping Mick Parkin in his heavyweight debut at UFC 332, Walker called out Marcin Tybura, and the name is popping up everywhere from Sherdog to MiddleEasy to Yahoo Sports, all carrying the same callout. The finish itself was quick work. Walker put Parkin away with a knee in the first round at the 3:35 mark, an explosive first impression at 205 pounds up. Our Elo model has Walker at 1524 over seven bouts, while Parkin sits at 1553 across six, so this was no soft touch for Walker to pad his record against. Tybura, if he answers the callout, brings a different kind of test. A Walker-Tybura pairing would be a notable gauge of whether the knockout over Parkin was a one-off or the start of something real at heavyweight. There's a family subplot running alongside all this. Johnny's brother Valter Walker, ranked eleventh at heavyweight and fresh off a first round calf slicer submission of Thomas Petersen, has been positioning himself as a kind of bodyguard for Johnny in the division. According to Ag Fight, Valter has already responded to a challenge from division rival Steven Asplund, who is unbeaten in his last outing with a decision win over Guilherme Pat and carries a 1544 Elo rating of his own. Fans are already buzzing about Walker's move into heavyweight, with the weekly recap thread on r/MMA flagging it as one of the week's bigger talking points. Whether the UFC lines up Tybura next, or Valter and Asplund end up colliding first, the Walker family has suddenly made heavyweight a lot more interesting to watch.