Shamhalaev (10-1) showed quick hands from the start and caught Richman (12-2) with a counter right that crumpled the American 145-pounder to the canvas. He followed with a couple of punches before referee Yves Lavigne stepped in at one minute 45 seconds.
Richman took his time regaining his feet and was taken to hospital after the fight.
The Russian will meet either Wagnney Fabiano (15-3) or Rad Martinez (13-2) in the tournament final. They fight Nov. 9 at Bellator 80 in Hollywood, Fla.
Tournament winners in Bellator earn US$100,000 and a title shot.
In a heavyweight semifinal, American Rich (Rare Breed) Hale stopped Thiago (Big Monster) Santos at 3:31 of the first round.
The six-foot-four, 238-pound Hale was giving up bulk to the six-foot-three, 265-pound Santos and the big Brazilian charged him with wild throws when the fight started.
Hale, moving up from light-heavyweight, weathered the storm and managed to get the Brazilian to the ground after the two collided. The fight ended with Santos on his knees, trying to protect his head as Hale (21-4) punched away from the top.
Hale, by virtue of his fourth straight first-round finish, takes on either Alexander Volkov (17-3) or Vinicius (Spartan) Queiroz (6-2) next.
Santos (11-2) was coming off a painful victory over Eric Prindle at Bellator 75, a winner by disqualification after talking an axe kick to the groin. He said he lost a tooth and had several others loosened by Hale.
The mixed martial arts show, Bellator's fourth at Casino Rama, was hit by the earlier withdrawals of Brazilian bantamweight champion Eduardo (Dudu) Dantas and English welterweight Paul (Semtex) Daley. Dantas was recovering from an August KO at the hands of Tyson Nam while Daley had visa issues.
The card drew a crowd of 4,200 to the casino north of Toronto but not everyone was thinking of MMA.
"We want hockey," yelled one fan during a slow portion of an undercard bout.
The ring announcer reminded the crowd several times that 2,500 gambling machines lay just beyond the doors after the fight card.
Earlier, Douglas (The Phenom) Lima dominated American Jacob (Kobe The Stunna) Ortiz before stopping him with a vicious attack at the fence with just 10 seconds remaining in a fight contested at a catchweight of 180 pounds.
The American-based Brazilian, who was coming off an April loss to Bellator welterweight champion Ben Askren, floored the unorthodox Ortiz with a right early in the fight but couldn't finish him after a length battle on the ground.
Ortiz had little offence and when he attacked, Lima punished him with crisp strikes. Lima hurt Ortiz with a knee and was pounding away when the second round ended.
Lima (22-5) picked Ortiz apart with his jab in the third, bloodying Ortiz's face under his skunk-like two-tone Mohawk hairdo. The fight eventually ended after Lima knocked Ortiz (13-4) back into the fence, following up with a flying knee and a flurry of punches.
"The guy's got a head made out of bricks," said Lima, who outstruck Ortiz 89-19 according to Compustrike.
Edmonton welterweight Ryan (The Real Deal) Ford won a unanimous (29-28, 30-27, 30-37) decision over iron-chinned American Kyle (Alley Cat) Baker.
"In all my 23 fights, he's the toughest guy for sure," said Ford, who threw everything he could at Baker but couldn't finish him.
Ford (19-4) swarmed Baker from the get-go, cutting him before the fight was a minute old with some nasty ground-and-pound. But Baker somehow hung on and survived a pounding at the fence to make it to the second round after the doctor checked him out.
Baker (12-7) took another pounding to start the second but unbelievably had Ford in trouble on the ground as the round wore on.
The American came out for the third, his face battered and swollen, and came at Ford, who eventually took him down several times. But Baker reversed position to mount Ford and then took his back. Ford muscled his way out to take top position and finished the fight pounding away.
According to Compustrike, Ford had a 48-13 edge in significant strikes over the fight.
Baker was originally scheduled to fight Daley but was switched to face Ford, who has now won two straight in Bellator.
Montreal welterweight Christ (The Beast) Franck won a split (29-28, 28-29, 29-28) decision over Marcus (Lelo) Aurelio, a Brazilian fighting out of Vancouver. The bigger Franck (4-0) started the first two rounds strongly but faded in both as Aurelio (6-2) took control. But Franck kept pushing in the third, doing enough to stop Aurelio's win streak at six.
Montreal lightweight Guillaume (Il Toro) DeLorenzi (10-1) was dominant on the ground as he choked out American Jonny (The King of Late Night) Carson (10-6) at 4:49 of the first round.
Unbeaten Russian heavyweight Vitaly Minakov (9-0) stopped Vladimir Starcencov (3-1) of Laval., Que., via TKO at 27 seconds of the second round.
Russian lightweight Magomedrasul Khasbulaev (18-5) submitted American Josh Pulsifier (17-8) via rear naked choke at 3:30 of the first round.
Josh (The Juggernaut) Appelt (8-2) won by TKO over Ed Carpenter (5-4) at 3:20 of the first round in an all-American heavyweight bout.