Jayson Tatum's health status is the major question of Game 7. AP No one saw this Game 7 coming. After the Celtics led the 76ers, 3-1, in a best-of-seven, they dropped two straight to Philadelphia and looked terrible in every facet of Games 5 and 6. The 76ers are still 7.5-point underdogs across the sports betting market going into Game 7 after it opened as high as 8.5 before some money came in and moved the line. It’s a lot of respect to give a Boston team that has shot 41.1 percent from the field spanning its last two games and a terrible 28.6 percent from beyond the arc. Those two figures are the bottom four in the NBA among playoff teams, none of which are top seeds. The underlying factor here is whether Jayson Tatum is injured; there were mixed reports about whether he strained his calf during Game 6. If Tatum is injured, the Celtics are in disaster territory since they can’t allow their best player to tear his other Achilles during the playoffs after last year’s crushing injury.…