STARKVILLE, Miss. (AP) -- Auburn's senior stars made the difference down the stretch.

Doc Robinson scored 14 points and Chris Porter hit a 3-pointer with 25 seconds left as Auburn (No. 5 ESPN/USA Today, No. 4 AP) beat Mississippi State 51-45 Sunday.

"Like I always say 'Big-time players step up and make big-time shots,"' said Porter, who surprised his coach and teammates, along with Mississippi State, by launching a 3-pointer in the waning moments.

With 19 seconds left on the shot clock and Auburn nursing a four-point lead, Porter was left alone in the corner.

"He made one that wasn't designed," said Auburn coach Cliff Ellis, who was standing just a few feet from Porter. "But I knew when it left his hands that it was going in."

"I think everybody was surprised," Mississippi State coach Rick Stansbury said. "I think Cliff (Ellis) was more surprised then I was."

"It came at a critical time," Porter said. "I was wide open so I just took the shot and it went down."

The Tigers are the only team in the Southeastern Conference that start four seniors. In fact, Auburn is the only SEC team that has more than three seniors on the roster.

Ellis said it helps having players who have been there before.

"They've done it so many times," Ellis said of Porter and Robinson. "That's why they are heralded. That's what separates them."

On Tuesday, Auburn beat Kentucky for the first time in 10 years. Porter had 22 against the Wildcats, and Robinson made the game-winning 3-pointer in the closing minute.

The Tigers (15-1, 3-0 Southeastern Conference) looked like they still had a Kentucky hangover on Sunday. Auburn shot only 35 percent from the floor and missed numerous open opportunities.

Porter had a hard time getting shots off against Mississippi State's collapsing zone defense. The power forward was only 3-for-6 from the floor.

And the Tigers' shooters rarely made the Bulldogs pay for double teaming in the post.

But Robinson broke a 43-43 tie with 1:11 to play on a 3-pointer. Then Porter's 3, just his third of the season and first in SEC play, sealed it.

Robinson, a four-year starter at point guard, said he becomes more focused during crunch time.

"I love the ball in my hands with the game on the line," he said.

Despite going 14:44 from the end of the first half to about midway through the second without a field goal, Mississippi State (10-6, 2-2) took the lead with 4:36 left.

"We stood toe-to-toe, got back up on several different occasions when we had opportunities to lay down," Stansbury said. "Our kids struggled offensively and Doc Robinson and Chris Porter made huge plays in the last two and a half minutes. That was the difference."

After Auburn center Mamadou N'diaye fouled out with 6:08 remaining, Mississippi State center Robert Jackson scored two straight baskets -- the first tying the score, the second giving the Bulldogs a 40-38 lead and completing a 9-0 run.

Jackson finished with a game-high 15 points and 18 rebounds.

Porter then tied the score with a turnaround jumper in the lane. He finished with 12 points.

Auburn held the Bulldogs to 26 percent shooting, the Tigers' best performance of the season.

"We executed our defense about as well as we possibly can," Ellis said.

The Tigers won their seven straight against Mississippi State, including four at Starkville, despite being held to their lowest scoring output since totaling 42 against Temple in the first game of the 1997-98 season.

Robinson gave Auburn a five-point halftime lead by scoring two straight field goals in the final 40 seconds, the first on a baseline drive that he floated over the Bulldogs' big men.

Then Robinson closed the half by stripping Antonio Jackson of the ball and hitting a layup with 6 seconds left, making the score 25-20 at the break.