On Monday afternoon, Maria Sharapova held a press conference to announce that after this year's Australian Open in January, she failed a drug test. By Monday night, the governing body of tennis had provisionally suspended her—and so had Nike (NKE).

Sharapova tested positive for a medication called Meldonium, which WADA, the World Anti-Doping Agency, added to its banned substance list in January. Sharapova said she has been taking the drug for 10 years to help with her blood flow and did not know that it had been banned. At her press conference, Sharapova said she was not leaving the sport and hoped she would get a second chance to play it.

Nonetheless, she has been temporarily suspended by tennis, effective March 12, and Nike said it was suspending its endorsement deal with her late on Monday evening. Porsche and Tag Heuer followed suit. In a statement, Nike said, "We are saddened and surprised by the news... We have decided to suspend our relationship with Maria while the investigation continues. We will continue to monitor the situation."

Sharapova has earned $36.76 million in prize money in her career, but more than three times that amount off the court in endorsements. She has active deals with Avon (AVP) beauty products and Head rackets. As of Tuesday afternoon, those sponsors hadn't issued statements. Danone, which owns another one of her sponsors, Evian water, did release a statement on Tuesday, saying that it was "surprised" by the news. Evian "has been a partner of Maria Sharapova for many years, and until now, we have maintained a trustworthy professional relationship... We will follow closely the development of the investigation," Danone said.

What is perhaps most interesting here isn't that Nike suspended Sharapova, but how swiftly it did so. In other cases where Nike dropped an athlete over performance-enhancing drugs, it took days to make the decision, and sometimes weeks. It's curious that with Sharapova, the brand dropped the hammer in a matter of hours—especially considering the complexity of the situation.

Here are 5 other pro athletes who lost their Nike endoresements, plus one who, surprisingly, did not:

Adrian Peterson

Minnesota Vikings running back Adrian Peterson was indicted for child abuse charges on Sept. 12, 2014. Radisson Hotels ended its team sponsorship of the Vikings the next day. Five days later, Nike ended its personal endorsement deal with Peterson, saying in a statement that the company "in no way condones child abuse or domestic violence of any kind."

Ray Rice

After video footage leaked in February 2014 of Baltimore Ravens running back Ray Rice dragging his fiancé out of a casino elevator, sports equipment company Vertimax issued a wait-and-see statement, then dropped him in June. But it took all the way until September—when new video came out, nearly seven months after the scandal started, that showed Rice striking his fiancé—for Nike to end its endorsement. Dick's Sporting Goods (DKS) also pulled the player's jersey from stores, and EA Sports scrubbed him from its Madden NFL '15 game.

Lance Armstrong

News came out in October 2012 that the famous cyclist had taken performance-enhancing drugs, and while Armstrong at first denied it, sponsors didn't wait around to see. Nike was not the first to go, but it dropped him in under a week, along with, Anheuser-Busch InBev (BUD), Trek and others. Nike said that its company, "does not condone the use of illegal performance-enhancing drugs in any manner."

Michael Vick

The Atlanta Falcons quarterback was indicted for running a dogfighting ring in July 2007. A little over one week after the indictment, Nike suspended Vick and stopped marketing its Vick shoes and apparel, but it did not terminate its deal until one month later, in August. In a rare 180-degree turn, Nike gave Vick a new endorsement contract in 2011, after he had served prison time and returned to the NFL.

Justin Gatlin

In another sign that performance-enhancing drugs is one of the offenses Nike takes most seriously, the Swoosh dropped Olympic Gold medalist Justin Gatlin after the sprinter tested positive for steroids in June 2006. Like with Sharapova, the company's language was that it had "suspended" the runner's deal, not terminated it. Unlike with Sharapova, it took Nike two months, until August, to make the announcement. The New York Times later reported, in 2012, that even after Nike suspended Gatlin it continued to supply him with training equipment.

Tiger Woods

Nike doesn't always drop or suspend embattled athletes. The company famously kept Tiger Woods around, even amidst a mega scandal that changed golf forever, and despite criticism of the brand for what some saw as a double standard.

The Woods scandal began over the weekend of Thanksgiving in 2009, when the golfer and his wife Elin Nordegren were involved in a minor car accident. Weeks later, it came out that, in fact, Woods had cheated on his wife with many different women. Over a month later, when Woods finally held an apologetic press conference, sponsors like Gillette, Accenture, Gatorade and Tag Heuer ended their endorsement deals. Nike did not. The brand stuck by him, but as Fortune reported in 2011, it did cut his $20 million-per-year pay in half for two years as a punishment. Today, Woods is still sponsored by Nike.

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Daniel Roberts is a writer at Yahoo Finance, covering sports business and technology. 

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