Mike Woodson said Kidd's back is "just sore" and that, if needed, the 39-year-old point guard could have played against Orlando.
"We're being cautious and we're just taking it a day at a time," Woodson said.
Kidd's lower back has flared up in recent days.
He sat out of the Knicks' optional practice last Friday after feeling soreness following New York's win in Boston the previous day. He also left the bench in the second half of games against Philadelphia and Atlanta on Saturday and Sunday to get treatment and rest his back.
Kidd played just 15 minutes against the Sixers and five against the Hawks.
Woodson said Kidd has not undergone any tests to determine the extent of the injury. The coach says Kidd will "probably" play in the Knicks' next game -- Friday at home against Milwaukee.
The Knicks, according to Woodson, are taking a conservative approach with Kidd, an 18-year veteran. They originally listed him as questionable for Wednesday's game. Kidd told Woodson after Tuesday's practice that his back was sore and the coach decided to hold him out.
"We're going to rest him and see how he feels (Thursday)," Woodson said.
The Knicks can afford to be cautious with Kidd because Raymond Felton is back in the fold. Felton returned to the floor on Jan. 26 following a near-five-week absence due to a fractured right pinky.
"(Kidd)'s logged a lot of minutes since Raymond's gone down," Woodson said. "Now Raymond's back. We can be a little more cautious, I think. If Kidd says he's a little sore then I've got to be open-minded to that, rest him and welcome him back when he's ready to come back."
Kidd played 30-plus minutes in eight of the 12 games that Felton missed. Kidd also missed four games earlier in the season with lower back spasms. It's unclear whether this most recent back ailment is related to the previous injury.
Kidd, who signed a three-year contract with the Knicks over the summer, has been a driving force behind their strong start.
He is averaging 8 points and 3.9 assists in 28.5 minutes for the Knicks, who enter play tonight 1.5 games ahead of the Brooklyn Nets for first place in the Atlantic Division.
"Kidd's a big part of what we're doing here. And when it really counts, I'm going to need him," Woodson said.
Kidd was not available to reporters Wednesday morning.
Ian Begley is a regular contributor to ESPNNewYork.com.