Henrik Zetterberg is hopeful, but also realistic. Zetterberg would like to play in this first-round series against Boston, and because it doesn’t begin until Friday, he essentially has two bonus days to get well. But after having back surgery in late February, he knows this entire rehabilitation is a process with many unanswered questions. Zetterberg skated on his own Tuesday, prior to the Red Wings’ practice. He’ll skate with the team Thursday and will travel to Boston. “We have two extra days; the series doesn’t start until Friday -- we’ll see,” Zetterberg said of a possible return during the Boston series. “There are a lot of things that have to fall into place. Up until now, everything has gone well. Each step in the rehab has been good.” Zetterberg began skating on his own exactly one week ago. “I’ve skated for a few days and it’s felt good,” Zetterberg said.