This was the most severe slap upside the batting helmet that the Twins have suffered in the last hours before the start of a season since March 28, 1996, the morning that Kirby Puckett awoke with a mysterious dot in front of his right eye.

The loss of Ervin Santana means the Twins open this new season with a duplicate of the shallow, shaky starting rotation that doomed them in 2014, and basically has doomed them through four seasons with an average of 96 losses.

The key word there is “since,’’ as this is not an attempt to compare the loss of a 36-year-old Hall of Fame outfielder for the remainder of his career to a 32-year-old starting pitcher for a half-season.

The Twins of ’96 were coming off three losing seasons, including a 56-88 disaster in 1995, and tried to regain some faith with the fans by signing Paul Molitor that winter as a veteran designated hitter.

Then, Puck went blind in his right eye, and 78-84 was the best that could be done in 1996 despite the dual greatness of Molitor and Chuck Knoblauch.

The current Twins were dealing with a four-season disaster. Last Dec. 12, they tried to regain some faith with the fans by signing Santana to a four-year, $55 million contract that was the most expensive free agent deal in franchise history.

Santana came with an average of 199 innings pitched over the previous five seasons, and a 14-10 record with a 3.95 ERA for Atlanta in 2014.

He also carried a reputation as a good guy, and the enthusiasm that he expressed for baseball and its traditions was highly enjoyable.

Nobody would have imagined at the introductory news conference, or in his appearances at Twins Fest, or with his attitude in this spring training, that Santana also had respect for tradition when it came to the use of steroids.

On Friday, the commissioner’s office announced Santana had tested positive for a performance enhancer and would miss the first 80 games of the 2015 season. His PED of choice was stanozolol, an oldie but goodie for athletes choosing to cheat with steroids.

Most of us naïve civilians first heard of stanozolol when Ben Johnson, Canada’s gold-medal sprinter, was sent home from the 1988 Seoul Olympics in disgrace for testing positive.

Sticking to tradition, Santana and his agents also tried to sell the idea that the athlete was mystified as to how stanozolol entered his system. That’s a world-class level of bull slinging, since stanozolol is notorious as a muscle builder and not found in supplements.

Bottom line: You don’t test positive for stanozolol by accident.

So, now we know that Ervin Santana is worse than a fraud: He’s a lying fraud.

That’s probably redundant — as will be the Twins’ starting rotation in 2015, without Big Erv in the No. 2 slot and full of his vitamins.

The Twins’ starters had the worst ERA in the major leagues last season at 5.06. They did this despite Phil Hughes filling the role of a No. 1 guy with 32 starts, a 16-10 record, a 3.52 ERA and 209⅔ innings pitched.

Kyle Gibson had 31 starts and was so-so, Ricky Nolasco had 27 starts and was awful, and Kevin Correia had 23 starts and was Kevin Correia.

The remaining 49 starts were shared by eight pitchers: Yohan Pino (11), Trevor May (9), Sam Deduno (8), Mike Pelfrey (5), Tommy Milone (5), Anthony Swarzak (4), Logan Darnell (4) and Kris Johnson (3).

Yikes, in all cases.

There was legitimate optimism the combination of Hughes and Santana at the top, with Gibson looking improved and Nolasco much improved this spring, that the rotation could actually be an asset.

Now, Hughes has to be the same guy with the same immaculate control, and Gibson has to pitch with the consistency of a legitimate No. 2.

Nolasco has to be satisfactory 75 percent of the time rather than 25 (quite a jump), and then the Twins still will have to make it through the soft-tossing starts of Milone and the hits-filled starts of Pelfrey.

It probably will take only a couple of good starts at Class AAA Rochester for May to get back here, and Pelfrey to wind up in the bullpen.

That might help, but it won’t change this:

Santana’s cheating has the Twins back to piecing together a rotation, and with the level of starting pitching elsewhere in the AL Central, that means fifth place.

And fifth is bad news in a five-team division.