The signs were obvious as last season was winding down. Backup center Cristiano Felicio was regressing fast. Felicio went from averaging 18-plus minutes in January and February to getting limited playing time in the last few weeks, including a handful of games in which he didn’t even play. Still, general manager Gar Forman rewarded Felicio’s declining play with a four-year, $32 million extension last summer. How has it worked out? Felicio hasn’t played in the Bulls’ last three games and in five of their last eight. ‘‘I don’t know if it’s a step backward,’’ coach Fred Hoiberg said. ‘‘There are going to be times for Cris to get out there and make an impact for this team. The big thing is to keep himself ready, keep himself in shape, which he’ll do. ‘‘He’s been doing a good job staying after shootarounds, or he’ll stay after and get a good, solid workout. That’s the big thing right now is to keep his conditioning and keep his timing when his name is called.’’ Translation: Felicio has no real staying power in this rebuild. Twenty-five games into the regular season is enough of a sample size to see which players are solid pieces to move forward with.