There was a second-half-of-the-season tone in coach Jack Del Rio's voice when he spoke to reporters on Wednesday. Clearly, he's challenging his team to respond to its biggest game of the season, which would also seem to be the Houston Texans' biggest game of the season.

"We're both 4-4. Our entire division is up for grabs. The team that plays good football has a chance to take the division title. Everything you want as a football team is right there in front of us," Del Rio said.

It's the biggest game of the season for both teams because the winner will stay in the hunt for the AFC South title; the loser will fall into sole possession of last place and be forced to accept its dire consequences.

"Very important ballgame; it's crucial we come out of this game with a victory, somehow, some way," Del Rio added.

The good news for the Jaguars is that they would seem to be in peak condition for this Sunday's game. They're healthy, rested and coming off their best performance of the season.

"We're feeling good. We're not overconfident but you need to have confidence and this team does," quarterback David Garrard said.

Despite abysmal performances in three games this season, Garrard is the NFL's fourth-ranked passer with a 98.8 passer rating. He's thrown 13 touchdown passes and he's on pace to break the Jaguars' single-season touchdown passes record, 20 by Mark Brunell.

"He's been very good when he's been good and we seek to have more of the good. Him staying upright and being decisive, with the weapons we have we ought to expect to be a good offense. We need him to play well," Del Rio said of Garrard.

Del Rio especially needs his defense to play well this Sunday, against a Houston offense that is fifth-ranked (sixth in rushing and 11th in passing). Running back Arian Foster has come out of nowhere to lead the league in rushing yards (864) and rushing touchdowns (nine).

The Houston passing game is led by the combination of quarterback Matt Schaub to wide receiver Andre Johnson, who Del Rio referred to as the "best receiver in the game."

All of that will be a tall order for a Jaguars defense that is 28th in the league in total defense (22nd against the run and 28th against the pass). Del Rio is counting on what he believes is recent improvement on both sides of the ball.

"Just execute; play good football. That's what it's all about. We feel we're making strides. We're tightening things up in the back. We're better up front. Offensively, we're more than the Maurice Jones-Drew show," Del Rio said.

"What we have in front of us is a great opportunity," Del Rio added.

Each team has in front of it a win-or-else challenge.