Defending champions Ajax will face FC Twente in the Dutch Cup final after thumping second-division club RKC Waalwijk 5-1 on Thursday.Waalwijk were completely outclassed in the semi-final at the Amsterdam Arena, with their lone strike coming from Ajax defender Daley Blind's own goal in the 27th minute.Swiss midfielder Siem de Jong netted a second-half brace for the hosts, though the result was largely settled in the first half when Mounir El Hamdaoui restored Ajax's lead six minutes after Blind tied the scores at 1-1.Lorenzo Ebecilio put Ajax ahead in the 13th minute with his first senior goal, the Netherlands under-19 international playing a magnificent ball inside the far post from a narrow angle on the right.Blind gave the hosts a brief scare when his clearing header looped over Ajax goalkeeper Jeroen Verhoeven and into the upper-left corner, but a poor defensive clearance just five minutes later left El Hamdaoui unguarded at the goalmouth and the Moroccan striker duly capitalised.Defence let Waalwijk down again in the second half as de Jong put up a quick-fire double, interrupted by Demy de Zeeuw's 58th-minute skidder under Waalwijk custodian Ohad Levita.De Jong got a wicked deflection from the six-yard box for his 55th-minute opener and made it 5-1 with an absolute pearler 30 minutes later, dancing his way through three defenders before firing a left-footed rocket beyond a despairing Levita.Ajax and Twente will meet for the final in May.