The Dragons dominated the first-half to lead 20-0 at the break before Hull pulled it back to 20-18 at the hooter, missed conversions from Michael Dobson the only difference between the sides.

Asked if his side escaped defeat, the coach said: "No, not at all. I thought we deserved to win. I don't think we got away with anything. We're through to the next round.

"If we played well, the 20 points we scored in the first half should have been enough.

"I didn't think of the score at half-time because we were in control of the game. The boys worked hard and fought hard and Hull KR played well.

"I don't think we got away with the win."

Robinson admitted the second half was not pretty to watch but is grateful his side had enough fight in them to secure the win.

"It was pretty tough watching the second half of defence and scrambled attack," he said.

"It was disappointing that we couldn't get a better rhythm in our attack. We just had to defend. I don't know if we got a penalty in the second half. We fought hard and that was a good thing."

Rovers coach Craig Sandercock felt his side missed an opportunity to advance to the next round of the Challenge Cup with their spirited second-half performance.

"I'm just dwelling on losing a game of rugby that we really should have won," Sandercock said.

"It's not every game you score more tries than your opponent and lose a game. It's devastating. When you score four tries to their three, you expect to win the game."

It was not the introduction to Challenge Cup rugby that Sandercock would have wanted and he now has to raise his side for the second half of the Super League season.

"When it's the first game, it doesn't feel like the Challenge Cup," he said. "If we had won and we drew a side not in Super League it would have raised the ante."