Sergio Nápoles Saucedo gave Pioneros an early lead by drilling a hard, low shot past keeper Brad Knighton in the second minute but by halftime the Revs had rolled up a 3-1 lead.
Shalrie Joseph won a ball in midfield and set up Smith for his first goal in the 11th minute, and Smith struck again in the 27th minute by putting away a feed from Twellman, who had controlled a cross from Chris Albright. Twellman, playing in his first preseason game this year, potted the third goal just before halftime after Pioneros had failed to clear a Smith free kick.
Mansally scored his fifth preseason goal in the 84th minute, putting away a pass from former Gambia under-20 teammate Sainey Nyassi. Revs coach Steve Nicol used 18 players and left out several regulars because of injuries or other reasons: Matt Reis (quadriceps), Steve Ralston (calf), Adam Cristman (toe injection), Spencer Wadsworth (ankle), and Rob Valentino (knee). Eight players, including six Revs, were cautioned.
The Revs, which began their preseason schedule in February by beating the Bermudan national team, 6-1 and 2-0 in Bermuda, get a stiff test Thursday against Mexican club Atlante in Playa del Carmen.