Lindsay Clancy‘s ex-husband testified in her defense during her murder trial, and now he’s sitting down for a big TV interview with “60 Minutes.”

The popular CBS program shared a teaser for the interview Wednesday afternoon … showing members of the “60 Minutes” team micing up Patrick Clancy before he sits for the interview.

Patrick looks nervous as he sits … before the teaser cuts to black.

The program captioned the post, “Patrick Clancy. This Sunday. Only on 60 Minutes.”

As you know … Lindsay’s case has captivated the nation — and has led to online users throwing out tons of theories that Patrick allegedly killed their three children and framed Lindsay.

Lindsay has admitted to the slayings … and her legal team has argued she was in the middle of a psychosis-fueled blackout … but people are still pointing fingers at Patrick — who has since remarried and moved from Massachusetts to New York.

Patrick’s attorney threatened legal action against people who spout the online theories … while Lindsay’s lawyer — Kevin Reddington — insists that people need to lay off Patrick.

Lindsay is still waiting to hear if prosecutors plan to bring charges against her again after the first trial ended in a mistrial. Patrick’s testimony during the first trial was in Lindsay’s favor … with at least one juror saying it definitely helped her case.

It will be interesting to see what all Patrick has to say.