In a picture the Rockets posted on their Twitter account, Harden can be seen wearing the face-covering sporting a black and white American flag with a singular blue stripe in the middle.

The color scheme has long been associated with “Blue Lives Matter,” a kind of counter-movement to the “Black Lives Matter” organization that has championed protest against police brutality and racial discrimination.

The use of blue in the flag is believed to be a nod to police forces across the U.S., which predominantly tend to wear blue uniforms.

A detail of Harden’s face covering drew particular attention online, as part of the mask covering the player’s nose features what appears to be a large white insert.

The way the mask is folded makes it almost impossible to determine whether the white insure is part of a larger symbol or simply part of the color scheme, one eagle-eyed user on Twitter suggested the mask may, in fact, feature a skull.

The mask Harden wore does indeed look very similar to a bandana called “The Blue Patriot,” which is available at Hoorag’s online store.

The emblem is based on the logo sported by The Punisher, the nickname Marvel Comics’ character Frank Castle is known as.

The symbol, however, has since been adopted by both military and law enforcement personnel. Several members of the U.S. Navy SEALs used it during the Iraq War, while the famed skull emblem became popular within the Blue Lives Matter movement at the end of the past decade.

In 2017, The Washington Post reported a variation of the symbol was used by protesters at the Unite the Right rally in Charlottesville, Virginia, in August of the same year. The rally descended into violence when participants clashed with counter-protesters and three people, including two state troopers, were killed.

Gerry Conway, The Punisher co-creator, has long condemned the appropriation of the symbol by law enforcement forces, describing it as disturbing.

“The vigilante anti-hero is fundamentally a critique of the justice system, an example of social failure, so when cops put Punisher skulls on their cars or members of the military wear Punisher skull patches, they’re basically sides with an enemy of the system,” he told Syfy in January 2019.

“They are embracing an outlaw mentality. Whether you think the Punisher is justified or not, whether you admire his code of ethics, he is an outlaw. He is a criminal. Police should not be embracing a criminal as their symbol.”

Predictably, Twitter was far from impressed with Harden’s mask.

It is of course perfectly possible that Harden may just be a fan of Marvel Comics and of The Punisher in particular, which is why he opted to don the mask. At the same time, however, his decision to wear a face-covering sporting the color scheme of a pro-police movement may strike some of his colleagues as tone-deaf.

In the wake of George Floyd’s killing in Minneapolis on May 25, several NBA players have been vocal in demanding social changes and calling for an end to racial discrimination. As a result, Harden’s latest sartorial choice may come under scrutiny.

The Rockets star isn’t the first high-profile athlete to cause controversy by wearing a “Blue Lives Matter” mask.

Just three days after Floyd’s death, Minnesota Twins outfielder Max Kepler posted a picture of himself wearing the face-covering, before deleting it and claiming he was unaware of the significance of the symbol.