Leeds rugby director Andy Key believes his side's 15-9 victory over Wasps was overdue reward for their improvement this season.

The Yorkshire side earned a first Guinness Premiership win since beating Newcastle in March 2008 thanks to five penalties from fly-half Ceiron Thomas.

Key said: "Our increased match-fitness since we were last in this league is playing its part.

"It was not the prettiest performance, but we gnarled it out and the players are delighted.

"We never stopped believing after a number of close calls this season. We should have won at Saracens last week but had a good try disallowed, for which we have received an apology.

"The most important Premiership game for us, however, is the next one. We are a team who are developing and growing."

Captain Marco Wentzel believes they can start hauling in the teams above them who, a month ago, believed they were going to be safe.

He said: "This is great for the club because we have been on the losing side so often this season and felt so frustrated.

"We were more disciplined in this game, a real team performance with no stars, just a love for each other and self-belief. This win has been coming.

"The guys are coming to terms with what it means to move up a division, and we are adjusting."

Leeds' former Wasps and England scrum-half Andy Gomarsall added: "It has been a long season already, so this win is a great reward for a lot of hard work, and to win at Wasps for the first time in our history is tremendous.

"I have been involved in rugby at this level for a long time, but still get a huge sense of satisfaction from playing in this environment."

Wasps were booed off after a dismal display for which they had only three Dave Walder penalties to show.

Not even the introduction off the bench of veteran lock Simon Shaw, 36, could inspire a fightback, although his return from a metatarsal injury is a rare piece of good news for England manager Martin Johnson.

Coach Shaun Edwards said: "You do need to give Leeds credit. They have been close to winning a number of times this season and unfortunately for us, they won here.

"Our set-piece was disappointing, particularly as we trained really well all week. Yes, we are a dry-weather team, but we are into the depths of winter now so we have to adapt.

"Leeds were never going to score a try against us, but we did not handle the conditions as well as our opponents."

Rugby director Tony Hanks agreed: "We put on pressure, but we were simply not accurate enough. Leeds put pressure on us in scrum and line-out, they really flew into us and technical mistakes proved costly. We lacked the composure we displayed winning at Gloucester last week.

"That was a special day for Leeds. Take nothing away from them, they really took it to us and deserved to win.

"This has got to be considered a wake-up call. We have a disappointed, frustrated and angry changing room because we have not performed well, haven't reacted well to pressure. A bad day at the office needs to be analysed."