Lyle Lovett must have a freakishly good memory, for he knows almost to the minute when he first heard his current touring partner, John Hiatt.

“You know, my introduction to John Hiatt was on the 31st of January, 1981, when I went to see Ry Cooder at the Paramount Theatre in Austin, when Ry Cooder was supporting his Borderline album,” the Texas troubadour recalls, calling the Straight while enjoying a day off in Winnipeg. “I’ve always been a big Ry Cooder fan, and my friends in a wonderful group from Austin, Uncle Walt’s Band—my friends Walter Hyatt, David Ball, and Champ Hood, who were all originally from Spartanburg, South Carolina—they were opening the shows.

“There were two shows at the Paramount that night; it was a Sunday night, and I drove over from College Station, where I was still in school. I was excited to see Uncle Walt’s Band, and then Ry Cooder, and Ry Cooder’s band for that tour was John Hiatt and John Hiatt’s band. Cooder kept throwing solos to this guy John Hiatt, and so I became a fan immediately, and went out and bought John’s records.”

There is, of course, the possibility that Lovett has recently researched his back story, but we’ll go with the idea that he has a singularly retentive brain. After all, this is a man who can remember what he and Bill Collings had for dinner the day they met back in 1978—egg rolls, served up by the esteemed guitar-maker’s wife—and who seems to recall every minute of every show that he and Hiatt have done since first sharing a stage in 1989.

Those initial performances, he goes on to explain, were songwriters-in-the-round affairs, with kindred spirits Guy Clark and Joe Ely. Time whittled the foursome down to a pair, with Hiatt and Lovett first playing as a duo after Clark began to show symptoms of the lymphoma that eventually killed him just last year. Their act hasn’t changed much since—yet at the same time, as Lovett explains, things vary enough from night to night that neither artist has ever been bored.

“It’s just him and me, on-stage together, and we sit there and we take turns playing,” he says. “And we talk to one another. That’s the format. It’s not a structured show; it’s not a show that we plan, or even tell each other what we’re going to play. I mean, we’re just sort of in the moment. John usually plays the first song, and my first song, then, is influenced by his selection.

“From the very beginning of the show, there’s an uncharted quality about it,” Lovett continues. “Over the years, we’ve gotten to know several of each other’s songs well enough to be able to join in, but I don’t know, from night to night, what he’s going to play. If he plays something that I sort of know, I’ll sing with him some, or play a little bit. That’s how it goes, and it’s great fun.”

As a bandleader, especially with his sublime, jazz-inflected Large Band, Lovett is known for demanding perfection, yet in these intimate concerts with Hiatt he seems to relish his partner’s unpredictability. The former Cooder sideman doesn’t necessarily belabour his hits—and when he does, they often appear in transfigured form.

“One thing that I find particularly interesting about John is that he will, from time to time, completely rearrange his guitar part for any given song,” Lovett relates with evident wonder. “Last night in Fargo, he played an arrangement on ‘Riding With the King’—and that was the first time he played ‘Riding With the King’ on this whole run, which started in January—and he played a guitar part that I’d never heard him play before. Not in a different key, but with different chord voicings.

“I tend to not do that. I mean, I play songs the way I made them up; once I’ve figured out ‘Okay, this is the song,’ it kind of stays that way. But John will reinterpret his songs, and I find that really interesting.”

Surprisingly, though, Lovett has yet to really figure out what makes Hiatt tick by attempting to write a song with him. Part of that’s logistical: the two of them travel in separate vehicles, which has the helpful side benefit of keeping their public rapport fresh. “We’re not having a manufactured conversation when we go out on-stage,” Lovett says. “It’s genuine, and I like that.” Still, he’s keen to find an afternoon when the two of them can sit down with their guitars in the hope that a song will emerge.

“We’ve talked about it, and we’ve kind of threatened to do it, but we just haven’t done it.” Lovett says, a little wistfully. “But I think it’s something that we should do, at least once.”

As for his own songs, Lovett says that fans can expect to hear excerpts from any of the 11 albums in his back catalogue. Just don’t hope to hear anything new. That’s not because Lovett hasn’t been writing on his own—he’s almost finished enough material for a follow-up to 2012’s cover-heavy Release Me, he reports—but because cellphone cameras make him nervous.

“Before the digital age, I always played my new songs, just because it’s fun to play your new songs,” he explains. “But I have not been doing that, because I want them to be new when I release them. In this day and time, if you play something once, all of a sudden it’s on YouTube, and it’s out there. That’s something that you do have to think about, unless you want your songs to be that familiar when your new record comes out.”

Lovett fans will just have to hold on to that promise of a new release—and take advantage of this opportunity to hear him in the company of an equally accomplished peer.

Lyle Lovett and John Hiatt play the Queen Elizabeth Theatre on Monday (March 6).