It has never been so clear, right out in front of everybody, at last, no denying it now, the conspiracy theorists are right:

Medical science is a Raider-hater.

Either that, or there are some (more) screwy things going on in Raidersland, I guess, though the conspiracy theorists are pretty sure it’s the medical science-hater thing.

The latest example happened Wednesday evening, when top Raiders signee Rodger Saffold — destined to be their left tackle in 2014 and possibly beyond — failed his team physical and had his five-year deal at a maximum of $42.5 million voided (and then went right back to his old team, the Rams).

Uh oh.

So the Raiders are now missing a left tackle … and that’s after letting incumbent Jared Veldheer (who most thought was better than Saffold straight up) go to Arizona for a deal less than the Raiders gave Saffold … and then had to rescind.

It’s possible that once the medical checks showed the state of Saffold’s shoulder, owner Mark Davis had second thoughts about this deal after general manager Reggie McKenzie’s previous sketchy forays with wounded players — D.J. Hayden, Matt Flynn, and others …

Or it’s possible McKenzie just didn’t know the extent of Saffold’s problem before offering all that money — and letting Veldheer walk away.

Or maybe something else happened. At this point, the end result is what matters and that means the Raiders don’t have a left tackle and that was one spot they actually had relatively covered a few days ago.

They used to have a young, talented defensive end — Lamarr Houston — but he left to sign with Chicago after the movement period began. He was far from perfect, but he was the best the Raiders had, and he was young. And he’s gone.

I will note that on Thursday, McKenzie regained a glimmer of momentum by signing proven pass rushers Justin Tuck (from the New York Giants) and LaMarr Woodley (from Pittsburgh) to two-year deals.

They’re good players, known leaders, and they will help the Raiders defense. The Raiders had the money, they might as well spend it on solid guys.

But the problem: Tuck is 30 and Woodley is 29. The guy they let go, Houston, is 26. Which one of the three do you think will still be at his peak when the Raiders might finally get good again in 2015, 2016 or whenever?

Obviously McKenzie and coach Dennis Allen need as many victories as possible this season after turning in back-to-back 4-12 records, but so far they have added zero foundation pieces or even marginal players who project to being as good in 2016 as they are now.

And they have lost two players who probably will be better in two seasons than they are now — Veldheer and Houston.

Quite a first few days of the free-agent period there, guys!

So McKenzie wasted crucial time on Saffold without getting Saffold — the Raiders got back their money but won’t get back the time.

Now they won’t get Veldheer back, either. And they are without a left tackle after ending the 2013 season with a perfectly decent one (in the eyes of most people except their own).

And McKenzie could have just franchise-tagged Veldheer and he would have been a Raider in 2014, and they could have focused on other positions of need — which is all the other positions.

So the Raiders have to go get another left tackle now (presuming they’re not ready to turn it over to Menelik Watson quite yet), either in the draft or in continuing free agency … and now all the best free-agent options are, of course, gone.

So they probably will have to use their fifth overall pick on a left tackle such as Texas A&M’s Jake Matthews, who is a very good player, no question.

But that means the Raiders can’t use the pick on an edge rusher. Or a receiver. Or a quarterback such as Johnny Manziel or Teddy Bridgewater.

And when you’re as talent-poor as the Raiders, you need to do everything to keep all options open. Not limit yourself needlessly, carelessly, foolishly.

The Raiders need to make a move after making a big move that was botched.

I ask yet again: What has McKenzie done in two-plus years that makes anybody think his next big move — or next 100 moves — will be the right one?

Read Tim Kawakami’s Talking Points blog at blogs.mercurynews.com/kawakami. Contact him at tkawakami@mercurynews.com or 408-920-5442. Follow him on Twitter at twitter.com/timkawakami.