Manager Joe Girardi and Jacoby Ellsbury said Thursday night the Yankees’ best player would be available to play Friday night against the Athletics after he left a 6-3 win over the Mariners with tightness in his right hip. They were correct: Ellsbury hit third and played center field and went 1-for-4, extending his hitting streak to 17 games, in the Yankees’ 7-0 win. “He came in and said he feels good,’’ Girardi said before the game. The problem first surfaced Sunday in Kansas City, Mo., while Ellsbury was running the bases. Ellsbury started Tuesday, Wednesday and Thursday in Seattle, but in the fifth inning Thursday, crashed into the center-field wall to deny Robinson Cano a possible homer or a sure extra-base hit to make a sensational catch. Ellsbury hit the padded wall and crumbled to the ground. He remained in the game, batted in the sixth and exited before the home seventh started. Ellsbury’s hitting streak is the longest in the majors. According to the Elias Sports Bureau, it ties the longest by a Yankees center fielder since Melky Cabrera hit in 18 straight in 2007.He is four short of tying a career-high 22 game hitting streak he had four years ago with the Red Sox.