It’s no secret that Bernie Sanders and Debbie Wasserman Schultz are not best friends.

First, there was the accusation that the Democratic National Committee was in Hillary Clinton’s pocket, intentionally scheduling debates on nights when fewer potential voters would be exposed to new candidates (see Sunday’s debate in Charleston, S.C.).

Then there was the data breach; The DNC cut off the Sanders campaign’s access to crucial voter data after alleging that Sanders’ national data director, Josh Uretsky, and his team improperly accessed data meant only for the Clinton campaign.

That frosty relationship appeared to be on display Sunday, when NBC cameras caught a brief, and very terse, handshake between Sanders and Wasserman Schultz. Was there even eye contact?

Sanders, of course, has surged in polls despite the perceived lack of television exposure, and his campaign has long since had its access to voter data restored. But if he wins the nomination – or even a few crucial early states – his relationship with the DNC chair will be an interesting one to watch.