Romo had a fumble and a team-record tying five interceptions, including two that were returned for touchdowns.
Phillips said it was just a bad day at the office for Romo, who had played like an MVP candidate the first four games of the season.
"I think he just had a bad day," Phillips said.
"Maybe he was trying to make big plays on them. The thing about Tony is I can't remember very many interceptions in practice at all.
"He is normally outstanding that way. It just seemed to be one of those days. I don't know why."
What Phillips liked and what the Cowboys liked was the way Romo never wavered or got down on himself. That was especially telling at the end of the game, when he was out there winging it and making plays to put the Cowboys in position for the comeback victory.
Romo completed 11-of-14 passes on the final two positions, leading the Cowboys to a touchdown and putting them in place for the winning field goal.
"I just think he had a bad day," Phillips said. "I will say this for him. At the end of the game he was still in there. That is what we preach. No matter what the stats are the most important thing is winning the game. That was the most important thing."
UPDATED INJURY NOTES: CB Anthony Henry had the boot removed off his injured ankle. But he is still doubtful for Sunday's game against the Patriots.
--WR Terrell Owens suffered a hip contusion against the Bills. He is expected to be ready for the Patriots game. But what Owens is most concerned with is three dropped passes against the Bills and just five receptions the past two weeks.
--LB Kevin Burnett suffered a thigh bruise against the Bills. But he should be ready for the Patriots game on Sunday.
--LB DeMarcus Ware had a 1.5 sacks and a forced fumble against the Bills. He has now had a sack in three straight games after having none in the first three.
No Concern Over Romo
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