CLEVELAND — Steven Matz didn’t even realize that he’d set a career high with nine strikeouts in Sunday’s 6-0 win over the Indians. Instead, in his first outing after the worst start of his brief big-league career, Matz took more satisfaction in something less glamorous.

Each time the Indians threatened against Matz, the Long Island lefthander stepped back, collected himself and thwarted trouble before it began.

The result: three hits in seven shutout innings.

“I think it was attacking the hitters, not pitching scared, trusting my stuff,” said Matz, who needed to rebound after allowing seven runs in 1 2⁄3 innings in his previous outing.

Matz allowed a two-out hit to Yan Gomes in the second inning and walked Marlon Byrd before getting Juan Uribe to bounce into a force.

In the fourth, Matz surrendered a leadoff double to Francisco Lindor, then retired the next three batters.

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An inning later, when Matz issued a two-out walk to Jose Ramirez, he responded by striking out Rajai Davis.

By the end of his seven scoreless frames, Matz had recorded at least one strikeout with his fastball, slider, curveball and change.

“It just shows what kind of competitor he is and how easy he can flush a bad outing like that,” catcher Kevin Plawecki said. “I know he put a lot of work in this week with [pitching coach Dan Warthen] and I know he was excited to get back on the mound.”

Manager Terry Collins said he could sense the frustration bubbling from Matz as he faltered with his fastball command against the Marlins. The moment had proved overwhelming.

“He might have learned a lot from his last outing,” Collins said before Sunday’s game. “He’s got to pitch. Even though you might not have command of one pitch, you’ve still got to pitch, you still have to go out and use all your stuff. He’s got a lot of weapons. So he’s got a lot of options to turn to, and I hope he does that today.”

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Against the Indians, Collins watched Matz change speeds and use his secondary pitches with confidence, even when behind in the count. Perhaps he had simply learned from his last start. Or maybe he benefited from a more comfortable routine; he made his previous start on nine days’ rest.

Whatever the reason, the manager saw the results he expected. Said Collins: “He pitched a great game.”