Donald Trump and his No. 2, Indiana Gov. Mike Pence (R), aren't on the best of terms right now. And things just got even rockier.

In Sunday's presidential debate, moderator Martha Raddatz pointed out that just a week earlier, Pence appeared to contradict his own nominee on Syria.

Trump, in response, didn't seem to care much about what Pence thought.

Some background on the issue at hand: In the Oct. 3 vice presidential debate, Pence said the United States should consider striking a key Russian military ally, Syrian dictator Bashar al-Assad. But far from striking Russian allies in Syria, Trump has indicated he'd be open to working with Russia in Syria.

But the disagreements between Pence and Trump go way beyond Russia. Throughout this campaign, Pence played the role of trying to course-correct Trump when Trump said something controversial. That often led Pence to say something that indirectly contradicted Trump, on everything from whether to endorse congressional Republicans, release tax returns and how to talk about the family of a fallen solider. Seriously, we have a whole list of where they diverge.

Whether to attack or work with Russia in Syria was just one of several instances in the vice presidential debate where Pence claimed the Pence-Trump ticket supported or believed something it did not.

Sometimes it feels like Pence and Trump have been running parallel campaigns. But up until this weekend, neither candidate had acknowledged just how much they disagree. Now, the gloves are off.

On Saturday, Pence said he "can't defend" lewd comments Trump made about women while on a TV show in 2005.  Pence's statement specifically referred to that audio, but as I wrote Saturday:

Pence may as well have been talking about this entire 2016 election. From the moment Pence accepted Trump's vice-presidential nomination this June, he's been in a sometimes-awkward, often-difficult, ultimately no-win situation: How does someone like Pence, a traditional social conservative with deep establishment roots, defend and champion the most untraditional and controversial major-party presidential nominee in modern history?

After watching Pence campaign these past few months, the answer seems to be a reality he acknowledged in part Saturday: He can't.

Trump, never one to back away from a fight, most definitely noticed his running mate didn't have his back. On Sunday night, it was his turn to throw a punch. And he did, by essentially dismissing the guy he shares a ticket with.

Publicly, at least, Pence remained seated on the Trump Train Sunday night.

But social media fired up when Trump so publicly disagreed with Pence. Stay tuned...