D’Angelo Russell is back in the lineup, and back in form. After missing two months following knee surgery, Russell has worked his way back into the Nets’ starting five. With just 20 games left — including Thursday’s game against the Kings — Brooklyn needs the budding young guard to keep developing toward becoming a cornerstone. “I feel great,” Russell said. “My body feels good.” Both his production and the eye test back that up. Russell is coming off a sterling all-around performance Tuesday in Cleveland, with a team-high 25 points, six assists, five rebounds and two steals. He finished a team-high plus-10 in 32 minutes. “Just being aggressive. Early in the game I saw the holes in the game that I could capitalize on,” Russell said. “Oh man, it was only a matter of time. That’s D’Angelo’s game. He can score, he can pass, play-make. There isn’t much he can’t do,” Rondae Hollis-Jefferson said. “It just feels good to have him back.” The Nets need him back for the rest of the season, as much for assessment as development. They’ll have four lead guards on the payroll for next season, and must figure out which ones can lead.