As the Miami Dolphins reach the midway point in their season, they've also arrived at a crossroads.

The Dolphins (4-4) began preparing Monday for two games in five days. With a sweep — and they'll likely be favored in both games — Miami will remain part of the AFC playoff race. Anything less, and the franchise turnaround led by new coach Joe Philbin could stall.

The Dolphins play host Sunday to Tennessee (3-5), then make their 2012 prime-time debut the following Thursday at Buffalo (3-5).

"We've had some good games, some not-so-good games, and some bad games," quarterback Ryan Tannehill said. "You have to realize where you are at and push forward. We are at a critical point in the season, halfway through, and it can go either way from here."

The Dolphins missed a chance to tie for the AFC East lead when they lost 23-20 Sunday at Indianapolis to snap a three-game winning streak. It was Miami's third three-point defeat, with the previous two coming in overtime.

Indy's Andrew Luck threw for an NFL rookie record 433 yards. The Dolphins have been outgained 1,341 yards to 793 in the past three games.

But Philbin said he's more worried about points than yards. While his team has outscored opponents 170-149, it has been outscored 60-31 after the third quarter.

"We've got to make more plays at critical times to win games," he said.

Other areas of concern include a shaky secondary and a ground game that has lost steam after an encouraging start.

Tannehill, by contrast, looks more efficient with each passing week. The rookie wobbled on the final series when Miami had a chance to rally, but finished 22 of 38 for 290 yards and one touchdown, while playing on a sore left leg that limited his practice time last week.

"I couldn't ask for a better job out of him," teammate Reggie Bush said. "He's really poised back there. I thought he played like a champion."

Tannehill struggled with interceptions early in the season, but hasn't thrown one since September.

"Don't jinx us," Philbin said with a smile. "That speaks to his decision-making. That's a positive."

Tannehill played well despite being sacked twice and hit half a dozen other times. Several hits were the result of lapses by Jake Long, and Philbin wasn't happy with the play of his Pro Bowl left tackle.

"Like the rest of the offensive line, it's got to be better," Philbin said. "Overall our offensive line play wasn't good enough, and he's part of that."

The Dolphins have netted less than 100 yards rushing each of the past five games, and Bush — who set a goal of leading the NFL this year — instead ranks 16th with 534 yards.

Bush had only 10 carries at Indy, in part because Luck and the Colts hogged the ball by converting 13 of 19 third-down situations. Philbin shook his head when asked to identify a defensive culprit.

"Where do you want to start? I wish we could put our finger on one thing," he said. "We used multiple calls, and they executed very, very well in that phase of the game, better than we did. It wasn't one thing. There were 19 third downs, enough to go around."

Third-down defense had been a strength previously this season, but the pass rush and coverage have been spotty all season. Opponents know it — they're averaging 44.5 attempts per game against Miami, most in the league. Luck threw 48 times without a turnover.

Cornerback Sean Smith, the anchor of the secondary, dropped a potential interception with the game on the line and gave up a touchdown pass. Cornerback Nolan Carroll — who has been filling in for the past month for injured starter Richard Marshall — was beaten repeatedly.

Personnel changes in the secondary are possible, Philbin said.

"We'll look at every available avenue we have," he said. "We've got to do better, no question about it."

The Dolphins have stayed relatively healthy, with the only season-ending injury involving guard Artis Hicks, who was sidelined in training camp while battling for a starting job. Philbin hopes to continue the trend by scaling back on physical work during the upcoming stretch.

"The wear and tear on the players' bodies is going to be a concern," he said. "We've got to make sure we're smart and figure out a plan to get ready to play this game, and another one four days after that. We need to be smart about our preparation."


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