A break from league business for cup action can help a club shake itself out of poor form. Killie's meeting with Dundee United tomorrow in the Scottish Cup is one that Chris Johnston can help kick-start Kilmarnock's league campaign. Sitting in the bottom two of the Premiership following a string of poor results, including last week's defeat to Motherwell, is not what Johnston and his team mates envisaged and he believes a win at Tannadice could be the boost Killie need for forthcoming games.The midfielder said: "We need to try to win this game and stay in the cup. If we get a good result, hopefully we can take that into next Saturday's game in the league and push on from there. We are still disappointed after last week's game but we know things can change with a couple of wins. Hopefully we can win this one. With the cup, you never know what can happen. Facing Dundee United will be a hard game but we know if we play well we can get a win."Johnston is not expecting an easy game when travelling to take on United at Tannadice but is confident about Killie's chances. He went on: "They are flying and we know all about their attacking threats. If we can keep them quiet at the back, we know we can go forward and attack ourselves. They deserve all the credit they are getting, especially the likes of Ryan Gauld, Andy Robertson and John Souttar, they are doing great. They are a great attacking side but we can get a good result. On our day, we can cause folk problems. We just need a break. We know if we play as well as we can do, we can beat Dundee United."Of course, on the other side of things, a side with good league form will be hoping to take that into the cup encounters. United manager Jackie McNamara is looking to his players to continue with their purple patch of form which saw them move up into fourth place in the Premiership thanks to last weekend's 4-1 win over Partick Thistle. McNamara has challenged his players to reproduce the form they have been showing in recent weeks as they bid to make it into the next round of the cup. He said: "It's a big game. We'll approach it as we do every one by trying to win it. Our form recently has been good, which is something we are going to try to continue. It's about what we do and we always focus on ourselves. This game will be no different, especially with what is at stake for the club. It's one we're looking forward to and hopefully it's a positive night for us."