Jeff Probst wouldn't underestimate Cirie Fields. Speaking to ET Canada, the host of Global's "Survivor" shared his thoughts on watching the show's legendary star Cirie Fields join "Big Brother" this season. [readmore label="READ MORE: " link="https://etcanada.com/news/1016308/big-brother-hisam-says-he-blames-himself-after-brutal-blindside-eviction-exclusive/" text="‘Big Brother’: Hisam Says He Blames Himself After Brutal Blindside Eviction (Exclusive)" /] "Look, there's a reason Cirie is…