EXPERIENCED efficiency in the shape of Derek Mountfield and the beauty embodied in Tony Daley's wing play sent Aston Villa into the sixth round of the FA Cup after a tenacious but overall disappointing Black Country derby at The Hawthorns yesterday. From the moment that West Brom's Gary Robson limped off in the fourth minute following a quite legal tackle from Kent Nielsen, the Second Division side's task took on an extra dimension their honest endeavour could never really fathom. Player-manager Brian Talbot found himself in the action fully an hour before he would have intended and was immediately confronted by the Villa formation that has taken them to a championship challenging position in the first division. The defensive phalanx of Paul McGrath, Derek Mountfield and Nielsen immediately reduced West Brom's attacking sorties to the wings which succeeded in finding launching pads but without ever negotiating a final penetrating effort. And when Kevin Bartlett's cross did slither across the penalty area after 20 minutes Mountfield cleared efficiently. It was at the other end four minutes later that Mountfield made his most telling contribution. The towering defender, reminiscent of times when he regularly added his presence to Everton's championship winning attacks for set pieces, raced through to meet Gordan Cowans's chip with a deftly placed header that found Stuart Naylor's net. West Brom bustled back at midfield where Bernard McNally fought consistently and McGrath cleared off the goal line while Colin West's header brought a comfortable save from Nigel Spink. The second half resumed with West Brom's pressure promising much but eventually delivering little. Don Goodman and Craig Shakespeare both had shots comfortably saved by Spink but the Villa 'keeper was relieved to see Brian Talbot head Albion's best chance of the game wide of the post in the 57th minute when for once the visitors' rearguard was clearly breached. West Brom's momentum slowed after that and Chris Price's bullet like header from Daley's cross in the 65th minute should have sealed victory for Graham Taylor. That effort by Price flew just the wrong side of the post but it underlined that Villa's range of attacking options does not rely entirely on England international David Platt. Indeed, Bobby Robson's latest midfield hope demonstrated flaws in his passing although he proved very effective in winning possession. Villa had to survive just one further anxious moment six minutes from full time but Cowans, on the goal line, pushed away Don Goodman's shot with Spink lost. The final and fitting say went to Daley, however, as he waltzed past two defenders and rifled his shot home, much to the delight of the visiting fans behind the goal. Significantly, it was a perfectly timed tackle by Paul McGrath on the edge of his own penalty area that began the move which saw lan Olney act as the link between source and finish. The Republic of Ireland international subsequently took the man of the match award. Alan Gunn's final whistle 90 seconds later brought to a conclusion a lesson that Villa look set to repeat before the end of the season. Their solid, rock like composition, porous in the proper way to soak up sustained pressure such as Albion's, has the appearance of a valuable and winning one.