Tech billionaire and Dallas Mavericks owner Mark Cuban has tweeted that he will be sitting in the front row on Monday night, representing for “Team Hillary” at what could end up being the most-watched presidential debate of all-time. While Cuban has fully endorsed Clinton and vocally dissed Trump as being unfit for the White House, the Shark Tank co-star hasn’t always been a #NeverTrump. In fact, Cuban is only about a year removed from saying publicly that the real estate mogul and former reality TV host might actually change the political landscape for the better with his run for the White House.

Over the past year, Cuban’s position on Trump has clearly shifted dramatically. Here’s a timeline showing how the opinionated tech billionaire went from being a Trump supporter, and even a possible running mate, to one of Trump’s most vocal social media haters.

July 2015: Praises Trump

A month after Trump first announced his latest bid for the White House, Cuban wrote on his Cyberdust app that Trump’s estimation of his own net worth was optimistic “bragging” at best. Cuban called Trump’s self-appraised net worth of $10 billion a “play number” and called the GOP candidate a “Paper Tiger” while questioning his business acumen.

But, later that month, Cuban did an about-face when he took to social media to praise Trump’s nascent presidential campaign as “probably the best thing to happen to politics in a long long time.” Trump responded on Twitter with a post that thanked Cuban and proclaimed Trump was “rapidly becoming a [Dallas Mavericks] fan.”

Cuban further stoked the flames of what appeared to be a growing bromance between himself and Trump later that month, when the Shark Tank star told the media that he would “consider” running as Trump’s vice-presidential running mate if he were asked. Cuban later walked that statement back, though, adding that he’s “not cut out for politics”

September 2015: Toys with entering the race

A year ago, Trump’s early GOP primary success drove Cuban to ponder what would happen if he entered the presidential race himself. Talking to reporters at the time, Cuban said he was frequently being asked if he would enter the race, calling it “a fun idea to toss around.” While Cuban didn’t sound likely to actually launch a campaign, he still seemed to like his chances, no matter his opponent. “If I ran as a Dem, I know I could beat Hillary Clinton,” Cuban said at the time. “And if it was me vs. Trump, I would crush him. No doubt about it.”

May 2016: “The guy at the bar who will say anything”

With Trump looming as the presumptive GOP nominee this past spring, Cuban appeared to still be supporting his fellow billionaire, but that didn’t stop him from getting in some jabs. At the time, Cuban joked about Trump’s bluster, claiming: “He’s the guy at the bar who will say anything to get laid. That’s Donald Trump right now. But it’s all of us who are going to get f**ked.”

June 2016: “The media was asking the wrong questions”

In June, Cuban turned up the intensity on his Trump criticism, at one point saying to the Dallas Morning News of Trump: “It’s rare that you see someone get stupider before your eyes, but he’s really working at it.” In an interview with Fortune that month, Cuban addressed his criticism of Trump, saying he was using Twitter to go after the issues of Trump’s wealth and fundraising because he thought “the media was asking the wrong questions.” Cuban also said Trump had reached out to him personally to ask why Cuban had gone so negative, but the Mavericks owner would not discuss how he responded to Trump.

July 2016: Joins the #NeverTrump train

A month later, Cuban finally admitted that he would not support Trump, calling himself a “#NeverTrump” on Twitter. Cuban also unleashed a Twitter rant during Trump’s speech accepting the GOP nomination for president, writing: “Dear world. Please ignore what the loud guy in the suit is saying. Americans are nothing like him. We love our country and are proud of it.” Earlier in the week, Cuban had showed up on CBS’ The Late Show for a show-opening sketch where he and Stephen Colbert rapped insults about Trump’s bank account and failed businesses.

By the end of the month, Cuban had officially endorsed Clinton for president in a speech in Pittsburgh, where he called Trump “a jagoff.”

August 2016: Denies being a stand-in

Cuban denied reports that he had been asked to act as a stand-in for Trump in order to help Hillary Clinton prepare for the upcoming presidential debates.

September 2016: Offers Trump $10 million to answer policy questions

In the weeks leading up to tonight’s debate, Cuban kept up his Twitter feud with the GOP presidential nominee while also predicting a stock market crash if Trump wins in November. After Trump called Cuban “not smart to understand what we are doing” in an interview, Cuban responded on Twitter with a challenge that would have him donate $10 million to charity if Trump agreed to be interviewed by Cuban on his economic and tax policy proposals for four hours. Meanwhile, after hearing that Cuban would attend tonight’s debate in support of Clinton, Trump tweeted (in what his campaign later said was just a joke) that he would invite Gennifer Flowers, the woman who allegedly had an affair with Bill Clinton decades ago, to sit next to Cuban at the event.

Given their long history of trading barbs, all that remains to be seen now is whether or not Cuban will continue his Twitter feud with Trump from the front row of the debate tonight.