The Voice UK 2018 contestants in the live shows were confirmed at the weekend with eight acts making it through.
This weekend they'll sing live for the first time and it'll be the public who decide which four make the final.
One of those four will go on to WIN in next Saturday's final, and Olly thinks the title is for anyone's to take.
He told Heat magazine: "I want to say myself but I do think Team will looks strong at the moment.
"But you can never tell. When I was on The X Factor, me, Danyl Johnson and Stacey Solomon were hot favourites for the first few weeks and then Joe McElderry came out of nowhere and won it.
"So, sometimes, it's not always the person you think."
Ahead of the semi-final, bookies have made Team Will the favourite to have the winning act.
Will.I.Am’s team is the one to beat as the Black Eyed Peas star has shortened further to be the winning coach and is now 4/5 from 5/4.
Sir Tom, who was the first ever coach to win the Voice UK with Leanne Mitchell when the show launched in 2012, is trailing behind as the second favourite at odds of 13/8.
Newcomer coach Olly Murs is an outsider at 7/1 alongside Jennifer Hudson, who is bottom of the betting at 8/1 to win.
Aoife Heffron, Spokesperson for BoyleSports commented: “Will.I.Am looks set for his second Voice UK victory, having won in 2014 with Jermain Jackman, as his odds to be the winning coach shortened all the way into 4/5 from his 5/4 price during the battle stages of the competition.”
She added “J-Hudd’s hopes of claiming back to back Voice UK wins have been dashed as she heads into the final as the longshot coach to win at 8/1.”
The Voice UK airs Saturday night from 8:30PM on ITV.