David Lennon David Lennon has been a staff writer for

David Lennon is an award-winning columnist and author who has been a staff writer at Newsday since 1991.

Forget last season. Whatever magic or mojo the Mets used to win the National League East and get to the World Series clearly has expired by now.

So to lean on those past accomplishments, however great, would be a mistake. This is a different year, a different roster, with its own problems and weaknesses. For the Mets to believe they’re going to repeat what they did — merely because they’ve already done it — is foolish.

This isn’t working. And if Sandy Alderson was under any illusions about this group self-correcting its flaws, the pitiful Braves showed him otherwise by completing a three-game sweep of the Mets with Sunday’s 6-0 beatdown at Citi Field. While it was a humiliating weekend for the defending NL champs, who couldn’t do much else right aside from tying their shoes, playing terribly in mid-June is rarely fatal.

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That is as long as the Mets tighten things up very soon, and that sense of urgency finally began to settle in after Julio Teheran’s one-hit shutout. Terry Collins can talk all he wants about tipping his cap to Teheran — “I know how it is here and it’s always our fault when we’re not hitting. That guy pitched pretty good.” — but this is not a new development.

The Mets have been a lousy offensive team this season, ranked 25th in on-base percentage (.307), 28th in runs scored (250), 29th in batting average (.234) and dead-last with runners in scoring position (.210). At times, they’ve been able to bully teams with 90 home runs, the sixth-best total in the majors, but the big-stick approach hasn’t been a sustainable model for success.

“You don’t want to panic early,” Collins said. “But right now, with what’s going on, we may shake some things up . . . We got to get better. We got to start playing better. We’ll see what we can do.”

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The Mets don’t get on base, and on the rare occasion that does happen, they’re stuck playing station to station because the roster possesses zero speed. Alderson can change that. If the Mets are lucky, the Rockies won’t find a trade for Jose Reyes, he’ll be released later next week and end up in Flushing, where Reyes would inject some desperately needed energy.

At the moment, however, Alderson seems more likely to go the in-house route, and Michael Conforto, slogging through an agonizing slump, may be perched in the crosshairs. Conforto had the Mets’ only hit Sunday, but he’s batting .119 (8-for-67) with 24 strikeouts in 21 games since May 24. And that’s with the Mets largely protecting him against lefthanded pitchers.

“Conforto is not going to sit here on the bench,” Collins said. “We’re going to look at every angle we can.”

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The Mets could flip Conforto to Triple-A Las Vegas for Brandon Nimmo, the No. 13 overall pick in the 2011 draft and the very first selection by the Alderson regime. Nimmo is just 23 — the same age as Conforto — and was hitting .327 with a .928 OPS at Vegas. He’s not likely to be a game-changer, but Conforto could probably use the opportunity to recalibrate in the minors.

Another possibility that could be gaining momentum is calling up Dilson Herrera (.290/.341/.498) to play second base and moving Neil Walker to third. The Mets have been reluctant to mess with their double-play combo of Walker and Asdrubal Cabrera, but it may come to that. Eventually, push comes to shove.

The Mets expect to activate Travis d’Arnaud for Tuesday’s series opener against the Royals, which will bounce Kevin Plawecki (.194) to Vegas, but that doesn’t feel like the antidote to all this. Sunday’s loss dropped the Mets into third place, behind the Marlins, six games in back of the Nationals.

When Collins was asked Sunday what he considers to be “late” in the season, he calmly replied the All-Star break. But that’s only three weeks away, and in the 20 games leading up to then, 14 are against the Nats, Cubs and Marlins.

The road to Panic City? If the Mets aren’t there yet, they’re approaching the exit.