A Dutch court has sentenced an Ajax fan to six months in jail after he ran onto the pitch during a Dutch Cup match and tried to assault an opposition goalkeeper, a report said on Thursday. An Amsterdam court convicted the 19-year-old, only identified as \"Wesley van W.\" of premeditated attempted assault after he tried to attack AZ Alkmaar \'keeper Esteban Alvarado last week, Dutch public television NOS reported. He will serve four months of the six-month sentence, with the remaining two months suspended for two years, the report added. Television footage of the December 21 incident showed Wesley van W. running onto the field during the last-16 tie and trying to tackle Alvarado, who then laid in with a couple of kicks before being pulled away. This led to the to the Costa Rican \'keeper being red-carded by the referee and the fan being escorted off by police. The expulsion infuriated AZ coach Gertjan Verbeek, who led his players off the pitch complaining about the lack of security at Ajax\'s Amsterdam Arena. The match was subsequently called off in the 37th minute. The game will now be played behind closed doors and without fans on January 19, the Dutch football federation (KNVB) said this week. The KNVB, which has since overturned the red card for Alvarado, also fined Ajax 10,000 euros ($12,940) and said the club face having to play an additional match behind closed doors - though that part of the sanction is suspended. Any appeal by Ajax to their punishment must be made by January 2.