​During her three varsity cross country seasons in the burnt orange of Eldorado, Gianna Rahmer has proven to be invincible.There’s not been a single race contested inside of New Mexico where she hasn’t finished first, and in just about every single one of those events, nobody has really challenged her supremacy in the Class 5A division. Rahmer’s long stride, smiling face and hot pink bandana crossing the finish line all by her lonesome, with no rival in sight, has become a rather standard snapshot in these parts.Might that scenario change this fall?The long-awaited arrival of Isla Rahmer is here. The 13-year-old eighth-grader at Hoover Middle School will be running varsity for Eldorado and is poised, several opposing coaches believe, to be a major challenger to her sister’s dominance.Even Gianna, the three-time defending 5A state champion, said she believes she and her sister are the state’s two best runners.“It might not be 1-2 every race … New Mexico’s talent is getting a lot higher, but we will definitely be 1-2 in a lot of races,” she said.Their debut together is Aug. 29, at Cleveland’s season-opening meet. This is where Gianna Rahmer burst — spectacularly, it should be noted — onto the state’s cross country scene, as she won that meet in 2023 as an eighth-grader herself.“I’m really excited (to become Gianna’s teammate),” Isla said. “I’ve been looking forward to it since the sixth grade, watching Gianna run. I’m gonna unlock things I didn’t know I could really do.”Isla has been a prodigious runner at the club level all around the country, with numerous national victories. The metro’s cross country community has been looking forward to this sibling pairing for a long while.“I am super excited,” Gianna, 16, said. She’ll be a junior this season. “It’s less running against her, more than I get to run WITH her in the same colors. Even in club, we never raced in the same age group, so I’ve never really gotten a chance to race her. To be two of the fastest girls with my sister and best friend, I’m so excited.”Lost a little bit in all of this is just how formidable Eldorado is going to be as a team this fall, and the Eagles’ depth chart extends beyond just the Rahmer sisters.Of course, the pressing question is, how closely the two will be matched around various courses.“I’m a little scared coming in as an eighth-grader,” Isla said. “But I have the capability of doing well against those people. I think having (Gianna) as a mentor as definitely made this transition running at Eldorado so much easier, because she’s done it. I can always go to her. And to do cross country with her makes me so happy.”Gianna, for one, thinks her sister won’t have much trouble adapting to competing against so many older girls.“She’ll be very competitive,” Gianna said. “She’s won a lot of national races, and so I don’t think she’s much of a darkhorse. People know her. People know the R