ANAHEIM, Calif. — Mark Vientos doubled to start a rally in the Mets loss Saturday . A day later, he became a one-man rally for the team. “I think the work behind the scenes is for sure showing these past two days,” Vientos said after smashing a pair of two-run homers in the Mets’ 5-1 victory over the Angels on Sunday . “I have been seeing the ball great all season. I think I have been just missing stuff, and I didn’t miss those two pitches today.” Vientos’ homer in the fourth following Carson Benge’s walk gave the Mets a 2-1 lead. In the eighth, Benge doubled in a run before Vientos again went deep. Mark Vientos connects on a home run during the Mets’ May 3 win. AP The outburst was welcomed by a slumping player and team. Vientos entered the day with a .650 OPS and had not homered since April 18. He’s become a regular in the lineup due to the Mets’ mounting casualties. “We have seen that,” manager Carlos Mendoza said. “We haven’t seen that in a while, but when [Vientos] gets hot, he can carry a team.…