TEMPE, Ariz. — Arizona Cardinals head coach Bruce Arians doesn’t expect the signing of veteran running back Michael Bush to immediately improve the team’s weak ground game.

But at 245 pounds, Bush gives the Cardinals a big, proven runner who might be able to help in a few weeks.

“The problem is we don’t have many padded practices left, so it will be very hard to get him up to speed as fast as we want to,” Arians said. “We didn’t sign him for this week. We signed him for the long haul, so we’ll have him ready when we need him. We’ll go from there.”

A seven-year veteran, Bush was released by the Chicago Bears in March and hasn’t been with a team since.

The Cardinals’ run-game woes go deeper than running back, but adding a bigger one could help. Andre Ellington, 199 pounds, has been carrying the load and he has played the entire year with a partially torn tendon in his foot.

The Cardinals miss Jonathan Dwyer, who was placed on the non-football injury list after being arrested on suspicion of domestic violence in September.

Robert Hughes, 235 pounds, has been used mainly on special teams and as a blocker.

It’s curious that the Cardinals waited this long to sign Bush. They’ve had a need for a bigger back for nearly two months now, and Bush was available that whole time.

“We’ve talked about him for three weeks now, maybe,” Arians said. “We have the opportunity to get it done, get him ready. Whether it’s a major addition or just a minor one, we’ll wait and see.”

The Cardinals are ranked 31st in rushing yards per game (3.1 yards) and Ellington is averaging just 3.3 yards per carry. A year ago, he averaged 5.5 yards per carry, the highest of any NFL back who carried at least 100 times.

The foot injury has limited Ellington’s practice time, which has impacted his performance, Arians said.

“You can’t play at this level without practicing,” he said.

SERIES HISTORY: 28th meeting. The Cardinals lead, 15-12, but the Falcons have won the past six meetings in Atlanta. The Cardinals haven’t won there since 1994. This game is the sixth matchup between the two teams in the last nine seasons and the fourth regular-season meeting in the last five years. In his last two games against the Cardinals, Falcons quarterback Matt Ryan has had nine passes intercepted, including four in the Cardinals’ 27-13 victory last year. He had five passes intercepted in 2012, but the Falcons won that game.

NOTES: WR Larry Fitzgerald could miss a second consecutive game because of a sprained MCL. Fitzgerald didn’t play last week in Seattle. It broke a streak of 110 consecutive games played that dated to 2007. Fitzgerald is missing practice time this week. … DE Ed Stinson has missed the past two games with a toe injury. He is missing some practice time this week and might not be able to play in Atlanta. … ILB Kenny Demens, a backup who plays on special teams, suffered a hamstring injury last week and is doubtful for the Atlanta game. … OLB Matt Shaughnessy, who is on the injured/designated to return list, is practicing for a second consecutive week. He is eligible to play next week against Atlanta.