Arsenal 1 Portsmouth 1About two hours after the final whistle, Thierry Henry was still sitting in the drug-testing room waiting to produce a sample. It was an apt comment on Arsenal's afternoon.

Hard as they tried, Arsene Wenger's players could not come up with the necessary and this was not a good moment for them to be reminded of their frailties.

Internazionale visit on Wednesday and here was an Arsenal display reminiscent of their struggles in the Champions League last season, when they drew all three home matches in the second phase and went out. Again, they were frustrated by well-organised opponents who closed down quickly and left no room for Henry to sprint into.

"You will see a different Arsenal on Wednesday night," Wenger promised, and the fans will hope so. It is time Arsenal proved themselves in Europe and the team could do without more disappointment before successive league games, starting on Sunday, against Manchester United (a), Newcastle (h), Liverpool (a) and Chelsea (h).

Portsmouth looked comfortably good enough to stay up. They disrupted their opponents' rhythm by getting quickly to the man in possession and kept bodies back, ensuring they were not open to rapier counterattacks.

Arsenal's laboured performance was probably not helped by the fact that nine of the 13 players they used had been on international duty. But Pompey also had a fair number away last week.

Patrick Vieira got into the game only after half-time without finding his best and Henry was as quiet as he often was in Europe last season. The shame for Arsenal was that Robert Pires was muted, his most notable contribution being the apparent dive with which he earned Arsenal a controversial penalty.

Lacking the ingenuity needed to regularly break down disciplined opponents, Arsenal scored only from the spot-kick. However, Portsmouth will upset others if they maintain this level and Wenger provided perspective from the top of the table. "I wouldn't say there's any reason to be alarmist," he said. "We have played five games and have 13 points and everybody would have signed up for that at the beginning of the season."

A clearer perspective on Arsenal's standing in the title race should be available next month after those testing fixtures. "I think we will be there and fight for it but you have to be realistic," Wenger said. "The fact that we didn't win it last year tells us we weren't good enough. We have to become good enough."

Defensively, doubts remain about Arsenal and they were grateful that Yakubu Ayegbeni's finishing did not match his otherwise impressive contribution. The Nigerian's pace and power troubled Sol Campbell and Kolo Toure but he failed to take any of three chances. In midfield, Pompey were tireless and fiercely competitive and there is technique as well as graft in their ranks.

Amdy Faye, the Senegal midfielder, was outstanding in the first half but tired, having been with his country to Japan. He and Nigel Quashie did much before the interval to ensure Vieira and the disappointing Edu did not impose themselves and it was no surprise when Teddy Sheringham gave Pompey the lead, finishing a slick move by heading in Steve Stone's cross. What was surprising was that Alan Wiley awarded Arsenal a penalty when Pires deliberately tumbled over Dejan Stefanovic's leg. Harry Redknapp called it "a terrible, terrible decision" and Wenger knew luck had favoured his team, who barely threatened before that.

Henry scored from a retaken spot-kick and Arsenal then did most of the pressing without meriting victory. Shaka Hislop saved well when required and Portsmouth defended solidly to deservedly stay unbeaten, with Arjan de Zeeuw a big presence. As Arsenal embark on a significant five weeks, they will need to do better.