KANSAS CITY, Mo. -- New York Mets right-hander Matt Harvey summed up his first career Opening Day start this way: “It’s not the ideal way to start the season.”

Harvey did not pitch poorly, but he did not dominate, either. He was charged with four runs (three earned) on eight hits and two walks in 5⅔ innings in what became a 4-3 loss to the Kansas City Royals on Sunday at Kauffman Stadium.

The unearned run scored in the first inning after Yoenis Cespedes misplayed a line drive in left field off the bat of Mike Moustakas and Travis d’Arnaud had a passed ball. The final run against Harvey scored after he departed, when Bartolo Colon allowed an inherited baserunner to score on Omar Infante 's single.

“He probably ran out of gas in the sixth,” manager Terry Collins said. “His velocity started to drop. All in all, I thought he threw the ball fine.”

Harvey struggled in his final three spring-training outings. He also dealt with a bladder infection last week, which he suggested prompted a blood clot in his urinary tract.

“At times I felt fine and other times it was just hard finding a rhythm and getting my release point,” Harvey said. “I made some pitches when I had to and wasn’t able to when I really needed to. So that’s a disappointment and pretty frustrating. Overall, my body feels fine. It’s not the way I wanted to start the season. We have to pick up from it and get ready for Tuesday.”

Harvey struck out only two batters. That matched the fewest of his career. He also had two against the San Francisco Giants on June 10, 2015.

“Did he have his A-plus stuff? No,” Collins said. “But he still threw the ball very well. And, as we know, they don’t strike out much. ... If we don’t drop the ball in the first, you look up in the sixth inning, he’s at 55 or 60 pitches. He made them swing the bat. He threw the ball over the plate. I was very happy with the way he threw.”