Jameer Nelson is on the Bulls. He really is. The veteran guard wore Bulls practice gear and everything as Sunday’s workout at USC concluded. He joined in a shooting drill and engaged in some easygoing banter with his new teammates. Whether Nelson ever dons his No. 14 game uniform is another story. Despite passing his physical Saturday, Nelson was unavailable to reporters, doing nothing to slow leaguewide sentiment that the Bulls aren’t done dealing. In fact, with league sources indicating that talks centered on Robin Lopez have intensified and also that the Bulls and Thunder have discussed at least Tony Allen’s expiring contract, management will be busy between now and Thursday’s trade deadline. The Bulls acquired Nelson, Allen, Omer Asik and — the prize piece — a first-round pick from the Pelicans on Thursday in exchange for Nikola Mirotic. Allen never joined the team and will be waived if he’s not traded. In a conference call with reporters that same day, executive vice president John Paxson said Nelson’s status is to be determined. It’s obvious the Bulls are keeping the expiring deals of Nelson and Allen in play as part of larger packages. Sources have indicated for weeks that Jerian Grant also is available. Still below the salary cap floor, the Bulls are well positioned to take bad contracts from other teams as long as a future asset — preferably a first-round pick — is attached. The bizarre vibe as practice concluded left coach Fred Hoiberg to answer questions about all the uncertainty surrounding the Bulls.