Bobby Portis might soon be asked to replace the most important defender the Milwaukee Bucks have had in a decade.
That's because the Bucks are staring down a painful offseason math problem: Brook Lopez is likely going to be a free agent, suitors are circling, and Milwaukee doesn’t have the money—or the margin for error—to easily replace him.
According to NBA insider Jake Fischer, there’s growing uncertainty that the Bucks will be able to retain Lopez, who’s now drawing real interest from the Lakers and Rockets.
The Lakers have been tracking Lopez for years. The Rockets, who nearly signed him away two summers ago, may take another swing if they lose Steven Adams. Both teams can outbid Milwaukee, and both have the minutes, roles, and urgency Lopez wants at this stage of his career.
If Lopez walks, all eyes turn to Portis as Milwaukee's starting center
On paper, Portis has the resume and the skill to step up to the starter's plate.
According to StatMuse, in nearly 100 career starts throughout his time in Milwaukee, Portis has put up norms of 16.5 points, 10 rebounds, and 1.7 assists per game, all while shooting an impressive 41.4 percent from deep. He’s a relentless worker, an emotional heartbeat, and one of the most consistent bench scorers in the NBA. He knows the system, the city, and the stakes.
But replacing Lopez isn’t just about numbers—it’s about anchoring one of the league’s most sophisticated defensive schemes. Lopez has been the backbone of Milwaukee’s drop coverage for years, allowing Giannis Antetokounmpo to roam free as a weak-side disruptor and protecting guards like Damian Lillard from constant exposure. His timing, discipline, and sheer size masked a lot of problems that don’t show up in the box score.
Portis is a different kind of player. He’s physical and fiery, but not a natural rim protector. His defensive instincts have improved under multiple Milwaukee Bucks coaching staffs, but he’s still vulnerable in space and doesn’t deter drives the way Lopez can.
Putting Portis at the five would require the Bucks to retool their defense, possibly abandoning drop schemes altogether, and rethink how they use Giannis, who has historically thrived next to a true shot-blocking center.
The thing is, there are no other options at the moment. After Antetokounmpo, the team's only remaining big-sized piece is the young Tyler Smith, who has the height but not the girth to actually play decent big man minutes. That will mean that Jon Horst will have to search for more athletic options in the free agency market willing to take a minimum deal.
It's a seismic identity shift if we've ever seen one. By the time the playoffs roll around, we could be looking at a completely different Bucks team; perhaps one with Giannis Antetokounmpo playing the center, and the undersized Portis playing power forward.
The gamble is real. But so is the upside. (At the very least, fans won't have to deal with the foibles of the Lopez-Portis frontcourt pairing anymore.)
Portis has long bristled at being typecast as a sixth man, and he’s said publicly that he believes he can start on a contender. His ability to stretch the floor, hit the glass, and inject energy makes him a matchup problem for traditional bigs. If the Bucks want to lean into a more mobile, offensive-minded identity, Portis could be the guy to lead that transition.
Still, it’s a risk Milwaukee didn’t expect to face so soon.
Lopez wasn’t supposed to be the piece that moved. But with age, injury risk, and the luxury tax all looming, tough calls are coming—and Portis might be the stopgap, the solution, or the scapegoat, depending on how things break. Milwaukee’s championship window is still open. But one wrong move at center could slam it shut.
Whether this becomes a dream role for Bobby Portis or the start of a defensive unraveling will define the Bucks’ next season—and maybe the Giannis era itself.