When Garth Brooks kicked off his World Tour three years ago, in September of 2014, he knew there would be plenty of highlights: the fans he and his wife Trisha Yearwood have gotten to meet, the cities they gotten to visit and more. But a highlight that Brooks could not have expected is a special tour guest: singer-songwriter Mitch Rossell.

Rossell, who has been out on the road with Brooks as of late, wrote Brooks' current single, "Ask Me How I Know." Brooks counts Rossell's part of his World Tour journey as one of the highlights of the entire trek.

"I think what I’m loving most though is the Mitch Rossell story right now ... just getting to watch him grow," Brooks recently shared with The Boot and other reporters. "Usually, on these arenas, he walks out, just him and a guitar, and nobody knows who he is. That’s balls right there; I couldn’t do it. So, watching him grow, I think, has been my favorite thing -- watching all these guys kind of take him in as a family.

"He’s a young kid. A lot of us have known each other more years than he’s lived. So for him to fit in as a young guy like that, it’s probably my favorite thing, to watch how the music does that," Brooks adds. "And somebody that dreams -- I love dreamers. I just do."

Brooks' concerts run more than two hours long, allowing him to perform many of his singles, including some of the early ones. Because Brooks was only 27 years old when his debut single, "Much Too Young (to Feel This Damn Old)," was released, he didn't understand many of his earlier hits as well as he does now, almost 30 years later.

"I think there were things in "If Tomorrow Never Comes" that a 27-year-old guy hadn’t experienced yet," Brooks shares. "That song, when I get to sing it now, especially getting to the age where now you’re starting to lose some of your buds, and I have kids too, I think that song really gets out there. I thought I had a pretty [good] grip on what "The Dance" meant, too, but for the same reason, I think the more you live, I think the more that song [means]."

Brooks will wrap up his World Tour with a string of shows at Nashville's Bridgestone Arena in mid-December. A list of his remaining dates is available on his website.

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