Classic rock is about heavy hooks, power chords and tight harmonies. But it’s also about letting loose and enjoying the good times. And there’s no better time for that than Friday evening, when we pick up our paycheck, punch out of work and enjoy a couple days of much-needed rest and relaxation.

The good times always feel a little better when you're listening to a guitar duel, which is right where this week's Weekend Songs artist comes in. While they ultimately became one of the more successful rock acts of the '70s, Thin Lizzy spent a number of years touring and recording to little acclaim -- years in which singer-bassist Phil Lynott and drummer Brian Downey found themselves repeatedly forced to cope with abrupt lineup changes that threatened to derail the band entirely.

But all that turnover ultimately led the group to guitarists Brian Robertson and Scott Gorham, whose complementary styles helped Thin Lizzy evolve into the FM-ready rock they honed to perfection on 1976's 'Jailbreak' LP. A Top 20 hit on both sides of the Atlantic, the record spawned a pair of the band's most successful singles in the title track and 'The Boys Are Back in Town,' but its strengths run deeper than the radio favorites.

In fact, the 'Jailbreak' LP ends with a pair of deep cuts that form one of the stronger one-two closing punches of the decade: 'Cowboy Song' and 'Emerald.' Both songs feature some of Gorham and Robertson's more impressive solos, but it's 'Emerald' that sends the album off on a high note with a thoroughly satisfying extended guitar duel.

"That was a riff that Phil had," Gorham later recalled during an interview with Songfacts. "It's got the real sort of Irish-y feel in it. Brian Robertson and I, we came up with the harmony guitars in there. But the main riff came straight out of Phil. It's a song about ancient times in ancient Ireland, talking about the warring clans and all that."

Whether or not you care about Irish history, it's the guitars that drive 'Emerald.' And as Gorham sees it, that's where he and Robertson started to develop their chemistry. "It was the first time that [we] did the bounce off lead guitar thing where he starts, I start, he starts, I start ... the back and forth," he explained. "That's the first time we actually got that one together. It felt so good and it felt so right, so we then started to try that out on a couple of other songs. That was kind of a launching pad for that style of writing between the two guitarists."

While subsequent efforts didn't fare as well on the worldwide charts, 'Jailbreak' has aged remarkably well. Aside from being a launchpad for Thin Lizzy's twin-guitar attack, 'Emerald' also makes a pretty fine kickoff for a couple days of not working. Down from the glen come the marching men, rockers, and they're bringing plunder, swords and flame. In the meantime, how about you scroll on up to that video at the top of the post, hit play, turn up your volume and let the weekend start now?

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