GREENEVILLE, Tenn. – Southern Oregon gave itself reason to believe it can contend at the NAIA Invitational by hammering the tournament's top-ranked team in pool play Thursday at the Greeneville Beach Volleyball complex.

The Raiders – seeded No. 8 at the eight-team final site – started their first Invitational appearance with a 3-2 loss to No. 4 seed Park (Mo.), but returned in the next session to handle No. 1 Ottawa (Ariz.), 4-1.

"We got off to a rough start to the tournament in the loss but closed it strong, then played a lot more like ourselves with a great response against Ottawa," SOU coach Paul Elliott said. "I think we settled in and should play with a lot of confidence moving forward."

Action continues on Friday with a modified schedule due to thunderstorms in the forecast. The Raiders (17-10 overall) meet No. 5 Arizona Christian in their final dual of pool play at 7 a.m. PT, then open single-elimination bracket play with a quarterfinal dual at either 9:30 a.m. or 11:30 a.m.

The Raiders' upset ended an 11-dual winning streak for Ottawa (16-4), which was last year's national runner-up, and the only match they dropped was between the 5-pairs. SOU's top-two pairs – Madi Gray and Tessa Zimmermann, Grace Gulbrandsen and Linda Conceicao – both won in straight sets, taking each of them but two points and three of four in extras. The 3-pair of Lucretia Benolken and Kira Sandoval overcame a first-set loss for its second victory of the day, and 4-pair Natalie Perez and Andressa Ribeiro Soares delivered SOU's first win in straight sets.

SOU fell behind 3-0 against Park but salvaged victories from Gray and Zimmermann and 5-pair Skyy Nihipali-Botelho and Kendal Hadwick. Those figure to be meaningful when seeding tiebreakers come into play on Friday.

Friday's first opponent, ACU, won 3-2 against Park and lost 5-0 to Ottawa in its pool openers.

(4) Park (Mo.) 3, (8) Southern Oregon 2
1. Madi Gray/Tessa Zimmermann (SOU) def. Izabella Ceratti/Maria Pim (Park) 24-22, 22-20
2. Grecia Ung/Aly Anderson (Park) def. Grace Gulbrandsen/Linda Conceicao (SOU) 21-10, 21-10
3. Luna Martins/Mafalda Bras (Park) def. Kira Sandoval/Lucretia Benolken (SOU) 21-11, 21-18
4. Carla Pons/Patri Ubeda (Park) def. Natalie Perez/Andressa Ribeiro Soares (SOU) 22-20, 21-18
5. Skyy Nihipali-Botelho/Kendal Hadwick (SOU) def. Daniela Gomez/Angelina Rodriguez (Park) 17-21, 21-19, 15-13

(8) Southern Oregon 4, (1) Ottawa (Ariz.) 1
1. Madi Gray/Tessa Zimmermann (SOU) def. Summer Hanks/Amey Rainaud (OUAZ) 23-21, 25-23
2. Grace Gulbrandsen/Linda Conceicao (SOU) def. Olivia Andersh/Eliana Dean (OUAZ) 28-26, 22-20
3. Kira Sandoval/Lucretia Benolken (SOU) def. Railey Dykstra/Amanda Carlson (OUAZ) 16-21, 21-12, 15-9
4. Natalie Perez/Andressa Ribeiro Soares (SOU) def. Grace Hughes/Shayna Martinez (OUAZ) 21-17, 21-14
5. Diana Enriquez/Shea Marovich (OUAZ) def. Skyy Nihipali-Botelho/Kendal Hadwick (SOU) 23-21, 21-16