Alonso finished in that position in Hungary last weekend, a place ahead of team-mate Lance Stroll.
The Spaniard was as high as seventh on the first lap, but he lost out to Sergio Perez and George Russell, both of whom were coming through the field after poor qualifying sessions.
Alonso, who logged six podium finishes in the first eight races of 2023, has accepted that Aston has now slipped down the order, with McLaren, Mercedes and Ferrari consistently ahead in the pack that is chasing Red Bull.
"Yeah, I think so," he said when asked if the Hungarian result was the best he could have achieved.
"I think we weren't quick enough to challenge anyone in front, and we didn't have any threats behind. So three points, ninth and 10th, maximum today.
"I think the last two races we are struggling a little bit. I think in Silverstone the safety car helped us in a way to finish seventh, which was a little bit better than our pace.
"In Silverstone and today, ninth probably is our pace. So yeah, behind the Mercedes, Red Bull, Ferrari and McLaren, which is more or less what we saw in qualifying, and what we saw in the race."
Alonso admitted that he was surprised that the pecking order was so consistent over two very different tracks.
"Yeah, a little bit," he said. "I think in Silverstone we did expect to struggle a little bit, but in Budapest we thought to be a little bit stronger. It was not the case. So we try to analyse and get back strong in Spa next week.
Source: Autosport