Lasswade High School is hosting the 2009 Scottish Senior and Junior championships and heavyweight Simmons will have to get past Glasgow Phoenix's Steve Lavelle.
Scottish National Youth coach Peter Harrison said: "I've entered Steve Lavelle to challenge Simmons despite the fact that he has had only six senior bouts.
"Fighting Simmons will be good experience for Steve, who will be coming to fight."
At light-heavyweight, Leith Vics' Tom Carter – fresh from beating the English boys club champion in Widnes last week – will face stiff opposition from Newarthill's Calum Johnson, Glasgow's James Cunningham and James Quigley, who burst Sparta star Jackie Kubas' championship bubble two years ago.
Lochend's reigning Scottish light-welterweight champion John Thain could be confronted by a dark horse from Hamburg, Ismet Beganovic. He represents Inverness Boxing Club and coach Lawrie Redfearn said: "He has had 40 bouts and has looked good in the gym so, if he draws Thain, it will be an interesting scrap."
Gilmerton have two youth champions in the title frame – southpaw featherweight Josh Taylor and British lightweight champion Conor McCallum.
But club boss Rab Young tipped Kirkcaldy's Keith Guthrie to win the senior welterweight title.
He said: "I've watched Guthrie all season and form wise he is on fire just now. Guthrie can expect a strong challenge from Leith Victoria's equally in-form Alister Hardie."
There are a total of 112 entries for the championships and clubs such as Midlothian and Craigmillar will make their biggest impact in the junior events, through fighters such as light-flyweight Dylan Moffat and light-welterweight Jason Easton respectively. Likewise, the Craigmillar-based Holyrood club will have entries at most weights.
Admission at the door costs 10 for adults and 7 for concessions and the first bout takes place at around 1pm.