By his usual high standards, it has been a rather subdued start to the 2020/2021 season for the six-time Ballon d’Or winner but his efforts against Bilbao were his eighth and ninth goals in 16 La Liga appearances this season, moving him level at the top of the goalscoring chart together with Luis Suarez, Gerard Moreno and Iago Aspas.
The win lifted Barcelona up to third on the La Liga table, although they are still seven points behind leaders Atletico Madrid, who also have two games in hand.
After a turbulent summer that saw Messi agitate for a move away from the club, Koeman feels the 33-year-old is getting back to his best.
"Since the first day that I arrived at the club I think Lionel Messi has given everything," the former Netherlands manager told a news conference.
"I haven’t been surprised by his quality because he's obviously been showing how good he is for years. It's possibly true that he's been less effective than normal which is why there could have been doubts but he's doing a lot better now, he feels comfortable at the moment and he feels up for the challenge.
"That's how I feel. But I think Messi is the one who can answer that best."
Barcelona are back in action on Saturday when they travel to Granada.
