Matt Doherty was disappointed the Republic of Ireland had only a 2-1 lead to show from their Nations League play-off first leg in Bulgaria on Thursday.

Ireland trailed to Marin Petkov's sixth-minute opener, yet they had turned the game on its head by half-time.

Finn Azaz's first international goal brought the visitors level, before Doherty nodded in three minutes before the break to put them in control.

The scoring stopped there, though, with neither side aiming a single shot on target in the second half.

While that meant Ireland came away with a narrow advantage, Doherty saw this as a missed opportunity before facing Bulgaria again in Dublin on Sunday.

"I think we believed already we could come here and win; belief wasn't a problem," he told RTE. "It's [about] proving to yourself you can go away and win, and that's what we did.

"But we know it's only halfway through; there's still a lot of work to do. We're a little bit disappointed it finished 2-1; we were wanting to push and put the game really to bed.

"When you leave it at 2-1 like that, it gives them a little bit of hope at the end with long balls and stuff like that. We're a little bit disappointed in the second half but happy to win, obviously."

Heimir Hallgrimsson agreed there is room for improvement ahead of the second leg at home.

"We can do a little bit better," the coach said. "It's only the first game of two, so we keep our heads on the ground and look forward to going to Dublin to play them at home."

Identifying Ireland's issues, Hallgrimsson added: "We got too passive in the second half, especially defensively after we pressed them well in the first half.

"It's always when you're leading, it happens automatically, but it shouldn't. We should be more brave when we're defending and step higher."