Stunning news, first reported by USA Today’s Mike Garafolo earlier today: 49ers key WR Michael Crabtree apparently tore his Achilles at the team workouts Tuesday afternoon and could be out for the 2013 season.

This is a massive development for several reasons, of course led by the assumption that the 49ers are more than capable of getting back to the Super Bowl (and winning this time) and that Crabtree — and his connection to QB Colin Kaepernick — is a major piece of that assumption.

Now: That Anquan Boldin acquisition sure looks better and better and … are you ready for a big role on a Super Bowl-driven team, A.J. Jenkins?

But there’s another part to this. Over the last two seasons of rabid success under Jim Harbaugh, the 49ers have been tremendously healthy, especially among their most important group of players, and have benefited from that health.

Really, there’s been only a handful of significant multigame injuries suffered by extremely important players over the last two seasons …

And one of them actually led to a big improvement and franchise revamping: Alex Smith’s concussion last season, which led to Colin Kaepernick.

Some of the other important injuries from 2011 to now: Patrick Willis at end of 2011 regular season (not major), Mario Manningham and Kyle Williams last year (both major, but they weren’t starters), Justin Smith and Aldon Smith at the end of last year (both major, but they both played through it at the end), Parys Haralson (major, but he wasn’t a starter) …

Also: Kendall Hunter (also major, also not a starter) and Brandon Jacobs last year and Braylon Edwards in 2011 (not major, not major contributors, either) …

Otherwise — and I point out the incredible health of the 49ers’ strong offensive line — the 49ers have been exceedingly healthy, and they have been smart enough and talented enough to take full advantage of that health.

Of course staying healthy isn’t just good fortune — it’s good work ethic to stay in shape, it’s good coaching, it’s choosing players likely to remain healthy … it’s all of that …

But in this violent game — where a non-contact OTA can lead to a major player ripping up his Achiles — staying mostly healthy for two seasons is also good fortune.

And today’s news is not anything close to good fortune for the 49ers or their offensive plans for 2013.

How do the 49ers replace Crabtree — who was by far Kaepernick’s favorite target last season and was considered so valuable that the 49ers targeted him at the goal line with their final three offensive plays of the Super Bowl?

Well, of course there’s Jenkins, who has bulked up some and now at the very least should be a top candidate for major playing time … after his 0-catch rookie season.

There’s Boldin, who can do a lot of the possession-route, move-the-chain stuff that Crabtree began to excel at the last few seasons.

There’s Manningham and Williams, but of course they’re coming off major injuries and may not be ready to participate at the start of training camp.

There’s Ricardo Lockette, Kaepernick’s workout buddy, who sure looks like a WR but nobody has any idea until he wins or loses playing time in camp or in games.

There’s tight end Vernon Davis, who often is used like a WR — especially deep — but seemed to sort of fall in and out of Kaepernick’s sight lines last season. Kaepernick’s fail safe (and his off-the-field friend) is Crabtree, and that’s where the connection is.

We’ll see if Kaepernick and Davis can form that same kind of bond — but Davis was an Alex Smith guy, for a long period.

And there’s Patton, the fourth-round pick out of Louisiana Tech, but it’s hard to count on any rookie to produce right away — just ask Jenkins about that. There are rookie WRs who put up big numbers right away, but usually those are future Hall of Famers, and let’s not say that about Patton just yet, OK?

Also, remember, that backup TE Delanie Walker left as a free agent.

And Randy Moss was not re-signed.

Harbaugh, Greg Roman and the offensive staff are very, very, very good at figuring out new ways and unveiling new packages to attack defenses … they’ve also got Kaepernick and the Pistol ready to go at any time …

But Crabtree was one of their rocks; again, just go back to the Super Bowl if you need a reminder about that. They had Kaepernick ready to go behind Smith, and now they’ve got a bunch of receivers they can try to put into Crabtree’s spot.

I doubt it will be as smooth as the Kaepernick move, though.

Read Tim Kawakami’s Talking Points blog at blogs.mercurynews.com/kawakami. Contact him at tkawakami@mercurynews.com.