How do defenders of baptismal regeneration understand Acts 8?

Acts 8:14-17: >“Now when the apostles in Jerusalem heard that Samaria had accepted the word of God, they sent Peter and John to them. These two went down and prayed for them so that they would receive the Holy Spirit. (For the Spirit had not yet come upon any of them, but they had only been baptized in the name of the Lord Jesus.) Then Peter and John placed their hands on the Samaritans, and they received the Holy Spirit.” For someone who claims that baptism fills us with the Holy Spirit (baptismal regeneration), how is this reconciled with this verse, which seems to indicate that baptism did not do anything?