Anderson traveled home to Florida this week to be with his wife, who was expecting the couple's second child.
The Senators announced the recall of Hammond from Binghamton of the American Hockey League on Wednesday, and the Ottawa Sun reported he would back up Lehner against the Detroit Red Wings.
"Nothing forthcoming at this point," coach Paul MacLean said after practice prior to the recall. "We'll wait to hear, and right now we're prepared for Robin to be the goalie, and if we need to bring Hammond or [Nathan] Lawson, we're prepared to do that. So right now that's where it stands."
Hammond is 17-12-3 with a 3.02 goals-against average and .903 save percentage in 33 games of his first AHL season.
Defenseman Erik Karlsson practiced Wednesday for the first time since returning from the 2014 Sochi Olympics, where he won a silver medal for Sweden.
"I thought he was a little slower, he just came 14 time zones," MacLean told the Senators website. "We were pleased that Erik skated today, it was his decision to come out and practice. I thought it was good, he had a good experience over there. Even though it was settling for a silver medal, it was still a good experience for him and that should be good for us."