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Can Athletes Return to Sports After Blood Clots?

Can athletes return to sports after blood clots? Serena Williams did and Chris Bosh could not. The difference lies in treatment, bleeding risk and the sport.

By Brett Hanson · Underdog Podcasts · November 6, 2026

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Rello Desaya has a beach rule: keep your shoes on. In the Circle The Block episode “Serena Came Back. Bosh Couldn't. Now It's Jalen Hurts,” he traces the rule to Serena Williams stepping on broken glass. That foot injury led to a health scare far beyond the cut itself.

Can athletes return to sports after blood clots? Yes, many can. Some finish treatment and return to full competition. Others need blood thinners for longer, making contact sports too risky. The clot’s location, the chance of another one and the demands of the sport all matter. No famous comeback can answer for another athlete.

Can athletes return to sports after blood clots?

Williams did. Chris Bosh did not. That contrast gives the episode its title, though it can make their cases sound like a test of resolve. Both wanted to play.

A clot can interrupt a career in two ways. A deep clot in a leg vein can send a piece to the lungs, where it may block blood flow. Then the usual treatment creates another problem for an athlete: blood-thinning medicine makes it harder to stop bleeding after an injury. A player can feel fit enough to train while still facing a serious risk from a collision.

The American College of Cardiology says athletes treated for a clot brought on by a known event often take blood thinners for three months. After treatment, many can return without a restriction tied to the clot. Repeated clots, or clots with no clear cause, can call for longer treatment. That changes the question for a basketball player taking elbows under the rim.

Why can a blood clot become dangerous?

Cunda stops at a word that sounds oddly reassuring: superficial. In the episode, he asks what a superficial vein thrombosis even means. The answer starts with where the clot sits. A superficial clot forms in a vein near the skin; a deep vein thrombosis, or DVT, forms farther inside the leg or arm.

Superficial does not mean imaginary. A surface clot can spread into the deep veins, though it does not usually travel straight to the lungs from a surface vein. A piece of a deep clot can break free and reach the lungs. Doctors call that a pulmonary embolism, or PE. Finding out where a clot is, and whether there is a deep one too, takes medical testing.

The symptoms can be easy to misread. The Centers for Disease Control and Prevention lists swelling, pain and warmth in a limb as possible DVT signs. Trouble breathing or chest pain can signal a PE and needs immediate care. Some people with DVT have no symptoms at all.

Cunda also asks whether clots only seem common among athletes because so many people get them. It’s a better question than assuming sport itself is the cause. An American Heart Association report says athletes, as a group, are not inherently more prone to these clots than everyone else. Surgery can put an individual athlete at risk. So can time spent unable to move. Long trips can, too.

Why do blood thinners keep players out of contact sports?

Blood thinners help prevent a clot from growing while the body slowly clears it. They also lower the chance of a new clot. The name is a little misleading: the medicine does not literally make blood thin. It reduces its ability to clot.

That is useful until a tackle or fall causes bleeding. In football, a hard hit can happen on any play. Basketball brings falls and collisions, even without shoulder pads. The American College of Cardiology advises against high-impact contact sports while an athlete takes anticoagulants because a blow can lead to serious bleeding, including bleeding inside the head.

Cunda puts the awkward trade-off plainly: “What's supposed to be helping the situation could be hurting you on the back end.” He is talking about treatment risk, not saying an athlete should skip treatment. Those are very different ideas.

There is room between playing a game and doing nothing. A doctor may allow some conditioning while ruling out contact. The exact plan depends on the clot, the medicine and the activity. Stopping blood thinners early just to get back on a field would leave the medical problem untreated.

“What's supposed to be helping the situation could be hurting you on the back end.”
— Cunda, on Circle The Block

How did Serena Williams return after a pulmonary embolism?

Williams cut her foot on glass in 2010 and needed surgery. Then came a pulmonary embolism in 2011, followed by a hematoma, a collection of blood, during her treatment. As Rello recounts the sequence, Cunda keeps coming back to the glass. Rello says it is why he wears shoes even at the beach. Cunda, for once, does not argue for bare feet.

Williams returned to tournament tennis at Eastbourne, England, in June 2011, nearly a year after her previous match. Her first win back took three sets. She lost her next match. The return was real, even if it did not arrive with a trophy and a neat ending.

The trophies came later. Her next Grand Slam singles title was Wimbledon in 2012. She won 10 of her 23 major singles titles after the 2011 scare, a number that surprises Cunda in the episode.

Tennis is different from football. A player can fall or get hurt on court, so it is hardly risk-free. But nobody is waiting to tackle her on the next point, which changes the calculation. Williams’s return shows what was possible for her, given her treatment and her sport.

Why did Chris Bosh stop playing basketball?

Bosh’s first known clot episode cut short his 2014–15 Miami Heat season. He returned the next season and played 53 games. Then another clot ended that season, too. His final NBA game came in 2016. He was 31.

He did try to come back. In September 2016, medical exams led the Heat to say he was not healthy enough to return for training camp. In February 2018, Bosh said publicly that he was still working toward a return. By February 2019, he said he was done pursuing one.

Cunda asks whether Bosh tried, then checks and corrects himself as the conversation goes on. That matters. It is too easy to tell this story as if Bosh accepted the end of his career the moment doctors found another clot. He spent years looking for a way back.

The distinction is cruel but clear. Being able to shoot, run and practice does not settle the risk of another clot or of bleeding during a game. Bosh had the skill to play. His health did not give him a safe route back to NBA basketball.

What does Jalen Hurts’s case tell us about returning?

Hurts is the episode’s present-day concern, not its answer key. On October 19, 2026, the Philadelphia Eagles and his agent, Nicole Lynn, said specialists in London had first found a superficial clot in his left calf. Later testing showed a DVT and clots in both lungs.

The statement said Hurts was stable and would take blood thinners. He could stay active around the team and continue to condition, but he could not take part in contact football while on the medicine. The team and Lynn said they expected a full recovery and anticipated that he could resume contact work once he was off it. An expectation is not a clearance.

Rello raises questions about how the situation was handled. Cunda wonders how Hurts could have played in London before the later diagnosis. Those are fair questions to ask. The public statement, though, cannot tell us every finding available to the doctors when they cleared him for that game.

Cunda ends with a simpler wish: let Hurts get well and be patient. Williams and Bosh explain why patience has no fixed finish line. One returned to a tennis court. The other kept looking for a basketball court that medicine would let him enter.

The full episode of Circle The Block is on Underdog Podcasts, with the rest of the network's shows.