Could be a double-colour-management issue, i.e. both LR and the printer think they should do the colour control.

If so, you need to check that only one is taking control of colour, preferably LR. There cold be some printer settings which need to be switched off, so that it only lets LR do colour mgmt.

Cornelia

Another possible cause:

You said: " the shooter was shooting Jpeg's".

What was his/her WB setting? Did he/she have Image Enhancements enabled in camera? Any other in-camera settings? High contrast? High saturation?

Have him/her shoot some Raw images and see if the problem persists.

In another thread where the poster reported strong red / magenta colors, Jeff Schewe said that this is an indication for double color management, i.e. Lr manages colors and the printer manages color. Cornelia-I also indicated this as the reason.

So, I would double and triple-check all my print settings in Lr and in the printer dialog to make sure that only one of the two is managing colors.

You know what? This sounds similar to another thread.

See here: http://forums.adobe.com/thread/1103249?start=0&tstart=0

But don't let the header of the thread confuse you; scroll down to where he shows his prints that are to light in red/magenta when printed from Lr but are OK when printed from CS6.

His was a Epson 4880 yours is a Canon 9500.

As you'll see on this thread no solution was ever found and the poster gave up eventually saying he would henceforth print from CS6.

The funny thing was though that once he disabled all his presets and plug-ins the Lr print was OK.

Somebody on the other thread mentioned an old print preset (old meaning a preset developed for a different printer if I remember correctly) that could have gone "funny" and did not allow the printer color management to be switched off.

I'm just mentioning this in case it would "ring a bell" with you.