After brilliant efforts in his first two big-league starts, lefthanded rookie Tyler Lyons has had increasingly diminshed returns in his last three outings for the Cardinals.

That probably will give manager Mike Matheny and pitching coach Derek Lilliquist at least pause as to whether they will leave him in the rotation to face the power-hitting Texas Rangers next Friday in St. Louis, although Matheny said after Sunday’s 7-2 loss to the Miami Marlins it was “way too early” to make that kind of determination.

Lyons allowed just one run over seven innings in his first two starts, both victories, against San Diego and Kansas City. But, in successive losses to San Francisco, Cincinnati and Miami, he has given up 14 earned runs in 17 innings. He walked .125-hitting Miami pitcher Ricky Nolasco twice in succession, one of them setting up a two-run inning.

“You can’t walk the pitcher,” said Lyons.

But Lyons said that wasn’t the worst thing that happened.

“Giving up six runs was worse than that,” he said. “But walking Nolasco. ... that’s definitely not something that’s going to help you be successful.”

Four of the six runs Lyons allowed in 51/3 innings came with two outs. The other two came in the first inning and Lyons said, “I never really got in a groove for the rest of the day.”

Matheny said Lyons was “just inconsistent. When he was making his pitches, he was down in the (strike) zone and he got some good outs. But a couple of mistakes really cost him.”

Giancarlo Stanton, who had six hits in the series, doubled to set up the two runs in the first. Juan Pierre, who also had six hits, singled home two runs in the fourth. Former Cardinal Placido Polanco doubled in two more in the fifth.

Lyons seemed ineffective, at times, pitching from the stretch and Matheny thought that Lyons’ timing out of the stretch position wasn’t good, notably because the Marlins had some basestealers in the lineup.