Etienne Barbara scored his league-leading 12th goal of the season in the 63rd minute and Nick Zimmerman doubled things up for the RailHawks with a 65th-minute goal.

Carolina (8-1-1) remains unbeaten on the road this season (4-0-0), and Saturday's win was their second of the year against Tampa Bay.

"This is a hard place to come and win, and we've managed to come in and do it twice," said RailHawks coach Martin Rennie in a statement. The RailHawks also won at Al Lang Stadium 3-1 on May 7.

"Tampa Bay (is) a good team, very difficult to play against. We worked hard tonight, showed a lot of character and managed to come up with a win. It's very encouraging now that we've got six wins in a row."

Not only have the RailHawks won six straight, they are also unbeaten over their last nine (8-0-1), matching the club record for most consecutive games undefeated.

The streak lived thanks to another standout effort from Brad Knighton in the RailHawks' goal. He made six of his seven saves in the first half, and Tampa Bay outshot the RailHawks 22-18 by night's end.

Tampa Bay (2-4-4) had the run of play early and had their best chance to crack the Carolina defense in the 21st minute. Pascal Millien forced a turnover deep in the Carolina end and played Mike Ambersley into the box. Ambersley ripped a low, left-footed shot to the far post, but Knighton got down to turn it away.

Ten minutes later, the RailHawks' best chance of the first half missed by inches. Barbara had a shot from 20 yards curl toward the upper corner of the goal and crash off the crossbar.

In the 45th minute, Tampa Bay saw a Mozzi Gyorio 20-yard free kick hit off the crossbar just before intermission.

As play went from end to end for much of the night, the first goal came from the penalty spot.

In the 62nd minute, Barbara received the ball in the middle of the area. Tampa defender David Hayes tried to knock it away from him, and as the two jockeyed for position, Barbara was pulled down and awarded a penalty kick. For the fourth time this season, he stepped to the spot and converted the try.

Roughly 70 seconds later, the RailHawks put the ball in the back of the net again.

Barbara spotted Brad Rusin racing toward the goal. Rusin's try was deflected away, and Jonny Steele ran down the ball near the endline to keep the play alive. He lofted it back across the box for Zimmerman, who ran onto it and headed the ball in for his second goal of the season (and Steele's third assist).

"That was a key moment," Rennie said. "The second goal gave us a cushion and they had to chase the game. Teams are vulnerable right after they allow a goal, and we were able to capitalize on that tonight. Jonny played in a good ball and it was an excellent header by Nick."

It gained far greater importance when Tampa Bay's Aaron King drew a penalty in the 86th minute. Ambersely converted the chance, cutting the RailHawks' lead to 2-1 minutes from full time.

With Saturday's results from around the North American Soccer League, the RailHawks exit the weekend with an eight-point lead at the top of the table. They'll look to widen the gap and remain undefeated on the road when they make their first-ever visit to Edmonton's Foote Field on Friday.

The club returns to WakeMed Soccer Park to play FC Tampa Bay at 7 p.m. June 18.