The Boston Celtics edged out the visiting Philadelphia 76ers 88–87 Wednesday night in a matchup of potential Eastern Conference contenders. Boston won their second straight and has won five out of the last seven games overall for a record of 12–10. The 76ers have cooled off losing nine of their last 12 games to drop to 11–11. Celtics’ Jayson Tatum scored 26 points on 9–20 shooting 3–8 three-pointers and a career-high 16 rebounds to lead Boston to victory. Dennis Schroder contributed 13 points in 30 minutes off the bench, on 4–12 shooting and 2–4 threes. Other Celtics contributors included Al Horford scoring 10 points and eight rebounds; Robert Williams III added 10 points on 5–7 shooting, and Jaylen Brown helped with nine points on 3–11 shooting. Horford has returned to Boston after signing with the 76ers in 2019. He then had his worst season, and was traded to Oklahoma City …