mcclen debuted for newcastle in 1999 against tottenham hotspur under the management of ruud gullit. gullit offered mcclen a long term deal which was promptly signed. he drifted out of the first-team picture for a few years, only to get a break in the team when injuries took their toll on newcastle. mcclen took his chance, including a goal against peterborough united in the fa cup, going on to make 10 more appearances in the 2001–02 season, including against arsenal in the fa cup. mcclen's performances that season, in which newcastle finished 4th, earned him another long-term deal which was promptly signed. however, mcclen struggled to retain his place in the first team before eventually being released in 2005 to carlisle united.