Using his educated jab, Collazo picked up the pace in the fourth-round scoring with big shots to the body.
Jerusalem did not come out at the bell for round seven and remained on his stool.
Collazo improved his record to 7-0; 5 and Jerusalem’s record dropped to 20-4; 12.
On the same card the WBO No 1 rated welterweight Alexis “Lex” Rocha 23-1; 15 stopped the No 10 rated Anthony “Juice” Young 24-3; 8 in the fifth round.
The time was 2:15.
In a lightweight bout, Oscar Duarte 25-1; 21 won on a seventh-round technical knockout over D’Angelo Keyes 17-3; 11. Duarte scored knockdowns in rounds three and seven.
Junior bantamweight John “Scrappy” Ramirez 12-0; 8 won on a split ten-round decision against Fernando “Leoncito” Diaz 12-4-1; 4.
The scores were 96-94 on two scorecards for Ramirez and 96-94 for Diaz.
LEIGH WOOD REGAINS WBA FEATHERWEIGHT TITLE
Leigh Wood 27-3; 16 regained the WBA featherweight title from Mauricio Lara 26-3-1; 19 with a 12-round unanimous points decision on Saturday night at the AO Arena in Manchester, England.
Only Wood was able to claim the title as Lara came in overweight and forfeited the title on the scales.
Lara was knocked down in the second round as Wood outboxed him.
The scores were 118-109 twice and 116-111.
JACK CATTERALL WINS COMEBACK FIGHT
On the same card, in his first fight since the controversial loss against Josh Taylor 15 months ago Jack Catterall 27-1; 13 outscored Darragh Foley 22-5-1; 10 over ten rounds in a junior welterweight fight.
The scores were 99, 98, 98, 89 and 97, 90.
In a female fight, WBA junior middleweight champion Terri Harper 14-1-1; 6 won on a ten-round unanimous points decision over Ivana Habazin 21-4; 7. The scores were 97-93 twice and 98-92.
OTHER RESULTS
Danny Ball W tko Jamie Robinson (welterweight) and Campbell Hatton W tko 5 Michjal Bilik (junior welterweight).
CHRIS BILLAM-SMITH WINS WBO CRUISERWEIGHT TITLE
The WBO No 1 contender Chris Billam-Smith 18-1; 12 won the WBO cruiserweight title when he beat defending champion Lawrence Okolie 19-1; 14 on a 12-round majority points decision on Saturday night at the Vitality Stadium in Bournemouth, England.
Billam-Smith scored a knockdown in the fourth and tenth rounds and Okolie was deducted points for holding in the fifth and seventh rounds.
The scores were 116-107; 115-108 and 112-112.
On the undercard junior middleweight, Sam Eggington 34-8; 20 won on a fifth-round stoppage against Joe Pigford 20-1; 19.
LUIS ALBERTO LOPEZ RETAINS IBF TITLE ON A FIFTH ROUND KNOCKOUT
Luis Alberto “El Venado” Lopez 28-2; 16 retained his IBF featherweight title when he smashed Michael “Mick” Conlan 18-2; 9 to defeat in the fifth round on Saturday night at the completely sold-out SSE Arena in Belfast, Northern Ireland.
Lopez dominated from the opening round and sent Conlan down and out at 1; 14 in the fifth round.
FIRAT ARSLAN WINS IN 70 SECONDS
Former world cruiserweight champion 52-year-old Firat Arslan 54-9-3; 39 who is rated at No 5 by the WBA knocked out Ibrahim Yildirim 11-4; 10 at 70 seconds into the first round on Saturday night at the Helios Arena, in Villingen-Schwenningen, Baden-Württemberg, Germany.
Arslan scored with a left hook that sent Yildirim down for the count.