Giants left-hander Derek Holland was recently demoted from the rotation to the bullpen, and it seems he's not happy about that, among other issues. Here's the money quote: 

Holland in late April sustained a bone bruise that landed him on the IL despite his objections. That would seem to be what the "fake injury" descriptor is getting at. GM Farhan Zaidi's response to Holland's comments, via Henry Schulman of the San Francisco Chronicle, seems to reinforce that interpretation: 

"He had a finger issue that he had back in spring training," Zaidi said. "It flared up. We got an MRI. He felt he could continue pitching. We felt it would be prudent to give him the time off. The decision was collaboratively made. We have extensive medical records of it.

"His use of the word 'fake' probably comes from him feeling he could continue to pitch with it. Players and the staff and front office people sometimes have differences of opinion when they should or shouldn't play."

On top of the injury kerfuffle and the demotion in role, Holland's also lugging around an ERA of 6.75 for the season, so it's likely frustration on multiple levels. Of course, Holland reportedly isn't the only one who's put off by Zaidi's roster decisions: 

It's a new front office, the Giants -- contrary to so much of the recent history -- didn't angle to contend this past offseason, and they're on pace for 96 losses. All that's adding up to some frustration in the San Fran clubhouse.