The San Gabriel Valley’s top two teams in the area’s girls basketball rankings, No. 1 La Salle and No. 2 Flintridge Prep, will meet in the first round of the CIF Southern Section Division 1 playoffs Thursday.

The CIF-SS used computer rankings for the first time to create the divisions and first-round matchups for the playoffs. The pairings were released Saturday.

La Salle (21-6) will host Flintridge Prep (19-1) in Thursday’s game. They met early in the season in the Glendora tournament, and La Salle won 54-44. For the Wolves, who are the Prep League champions, it is their only loss of the season.

Also in Division 1 is Bonita (21-6), which will have a tough task in the first round, as it goes on the road to play JSerra (17-10) from the Trinity League.

All first-round games are Thursday.

La Serna (18-10), which finished in a three-way tie for the Del Rio League title, is the No. 3 seed in Division 3A. La Serna will host Foothill (11-11) in the first round.

St. Lucy’s (12-12), an at-large team from the Baseline League, is the No. 3 seed in Division 4AA. St. Lucy’s will host Vistamar (11-9).

In the Division 2AA first round: Hacienda League champion San Dimas (18-8) will host San Juan Hills (17-11); Glendora (17-11), an at-large team, will be at Campbell Hall (13-11); Diamond Bar (13-6) will be at St. Margaret’s (19-9).

Two teams to watch in Division 3AA are Mission Valley League champion Keppel (19-9), which will be at Long Beach Jordan (16-11) in the first round, and South Pasadena (18-6), which will host Moorpark. If Keppel and South Pasadena win, they will meet in the second round.