Down two games to none in their best-of-7 playoff series with Phoenix, the Spurs face the Suns today as the Western Conference semifinal moves to Texas for two games.
"We've got to win two games here. We have to come in and take care of our own business," Lucas said Friday. "We just have to get back into a sync and a rhythm."
Phoenix leader Charles Barkley said the Spurs are similar to the Suns and he doesn't expect them to give up.
"They are going to come out and play hard," Barkley said. "They are like us. They're a good team and they're not going to quit."
Lucas is searching for the right combination to use against the Suns, a team he describes as small, athletic and quicker than the Spurs.
"We have tried to slow things down," Lucas said. "They've been able to counter any move we've been able to make so far, and they've had us making adjustments."
The Spurs have tried to play a passing game while concentrating on getting the ball inside to center David Robinson, who led the Spurs with 27 points in Thursday's 109-103 Phoenix victory.
Lucas said several other players will have to step up their contributions for San Antonio to win. And, he said, the Spurs have to avoid early deficits, which they faced in the first two contests.
"I've been a little frustrated because we've gotten behind early, so it's been really hard to help my team," Lucas said. "Although we get it back down to six or five points, we really haven't been in the game."
Spurs forward Sean Elliott said in addition to some offensive adjustments, including finding more ways for him and Dale Ellis to score, San Antonio must play better defense.
"They make their big runs here and there and eventually we catch up. As long as we stay steady we can win," Elliott said.
Phoenix is trying to continue with what has worked so far.