"We know after 38 games we may not still be second in the table... but maybe third," he smiled after seeing Nathaniel Clyne crash home the equaliser.
Southampton trail leaders Chelsea by six points after 12 matches and are two clear of third-placed Manchester City whom they play next.
"Until now Chelsea is the team to beat," Koeman told reporters. "And it's difficult because they have all the qualities in defending and attacking.
"It's up to the rest and we try to keep our position, to keep our way of playing because we believe in our way of playing."
Clyne's right-footed equaliser, after England goalkeeper Fraser Forster's ill-timed run had allowed Gabriel Agbonlahor to nip in and slot the opener, extended Saints' unbeaten run to six games in all competitions.
Koeman said the result, in terms of confidence, outweighed the point it was worth in the standings.
"Every game in the Premier League is difficult. We spoke about it before the game... they are in a difficult situation in the table and maybe that's more dangerous than normally," the Dutchman said of Villa.
"After (going) 1-0 down it was more difficult, but still we have one point and that's, for the feeling and the confidence, very good."
