The loss was a major setback to the Wolves playoff hopes. The team, which sits in sixth place in the West Division, will now need wins in each of their last two games for the possibility of earning a crossover into the North Division.
Forwards Andre Deveaux (G, A) and Jason Krog (G, A) scored for Chicago (38-30-4-6), while left wing Fredrik Pettersson added two assists. Goaltender Peter Mannino (16-17-4) matched a season high with 37 saves in the loss.
Chicago opened scoring, 1:55 into the game to take a 1-0 lead. Deveaux skated to the crease, took a feed from left wing Fredrik Pettersson and popped the puck past Peoria goaltender Jake Allen.
Chicago pulled to 2-0 when Krog came streaking down the slot and ripped a shot over Allen with 10 seconds left in the opening frame.
Allen (25-18-3) recorded 22 saves for Peoria.
Peoria (42-29-3-5) made the score 2-1, 5:23 into the second period when left wing Stefan Della Rovere wrapped around the back of the net and slipped the puck behind Mannino.
Right wing Akim Aliu tied the score, 2-2, for the Rivermen when the forward grabbed the puck in the left circle and shot it into the empty side of the net, 18:07 into the middle frame.
The Rivermen pulled ahead, 3-2 with a power-play strike 42 seconds into the third period when defenseman Nathan Oystrick one timed a shot past Mannino from the left faceoff circle.
Peoria increased their lead to 4-2 when center Anthony Nigro took a feed at the doorstep and flicked it into the empty side of the net, 12:55 into the final frame.
The Rivermen iced the win, 5-2, with an empty net tally with 1:44 left in the game.
The Wolves host the San Antonio Rampage at the Allstate Arena on Saturday at 7 p.m.
Chicago 2 0 0 -- 2
Peoria 0 2 3 -- 5
First Period---1, Chicago, Deveaux 22 (Pettersson, Krog), 1:55; 2, Chicago, Krog 19 (Pettersson, Deveaux), 19:50. Penalties---Della Rovere, Peoria (roughing), 5:16; Garbutt, Chicago (tripping), 8:47; Haydar, Chicago (slashing), 9:55; Redmond, Chicago (holding), 13:38; Shattock, Peoria (tripping), 13:38.
Second Period---3, Peoria, Della Rovere 8 (Peltier, Cracknell), 5:23; 4, Peoria, Aliu 9 (Nesbitt, Barriball), 18:07. Penalties---Della Rovere, Peoria (slashing), 8:52; Matheson, Chicago (roughing), 12:57; Aliu, Peoria (roughing), 12:57; Redmond, Chicago (tripping), 15:56; Ross, Chicago (hooking), 20:00.
Third Period---5, Peoria, Oystrick 15 (Hensick, Strachan), 0:42 pp; 6, Peoria, Nigro 9 (Nesbitt), 12:55; 7, Peoria, Drazenovic 22 (unassisted), 18:16 en. Penalties---Aliu, Peoria (interference), 1:00; Hensick, Peoria (high-sticking), 5:12.
Shots on goal---Chicago: 8-4-12--24. Peoria: 10-22-10--42. Power plays---Chicago: 0-4. Peoria: 1-4. Goalies--Chicago, Mannino (37-41). Peoria, Allen (22-24). A---6,179. Referee---Ghislain Hebert and Jarrod Ragusin. Linesmen---Brian Oliver and Mike Hamilton.