Novak Djokovic shook off jetlag to beat Andreas Seppi 6-3, 6-4 on Monday to help Serbia beat Italy 2-1 at the Hopman Cup then avoided injury after the match when a courtside barrier collapsed while signing autographs.Djokovic was signing autographs when the divider fell. It hit the Serb on his legs as it crashed and several fans went tumbling to the ground. Djokovic briefly squatted in discomfort but later took to the court for the mixed doubles, won by Italy 7-6 (4), 6-4.''It was a bit of a shock and I'm glad that the children involved are OK. I am fine,'' said Djokovic, who was more concerned about his condition pre-match because of fatigue from jetlag.Djokovic arrived in Perth less than 24 hours before he stepped on court, but still had a straight-sets win to add to Ana Ivanovic's 6-0, 6-4 victory over Francesca Schiavone, giving Serbia a win in the group-stage of the mixed teams event.''I arrived quite late last night and didn't get long hours of sleep and felt this morning like I'm dream-walking,'' Djokovic said. ''But as the match went on I was managing to get my rhythm. I broke the ice after the first set and felt a little bit better.''Djokovic got off to a good starting jumping out 2-0, but he later struggled to hold for 5-2. In the second set a double-fault gave Djokovic a break to lead 3-2, but he again struggled to maintain his lead and had to fight off four break points at 4-3 before completing his victory.