EVANSTON, Ill.- For only the third time in the history of the Midlands Wrestling Championships, a high school wrestler will compete in the tournament, held Dec. 29-30 at Welsh-Ryan Arena.     Alexander Tsirtsis of Griffith, Ind., has been accepted into the 41st Midlands. In his career, the senior has defeated several ranked college opponents in tournaments such as the Fila Junior World in Chattanooga, Tenn., and the U.S. Open in Las Vegas.     "I am pleased to get accepted into the tournament," said Tsirtsis, who will wrestle at 141 lbs. "I have been looking forward to competing in Midlands, and I have been training extra hard for it.     "Competing in the tournament is a great opportunity to get a head start in college. (Getting accepted into Midlands) is very flattering and motivational in my training. I'm definitely going out there to win."     Tsirtsis is preceded by Jimmy Carr of Erie, Pa., who won the 126-pound title in 1973, and Cary Kolat of Rices Landing, Pa., who entered the tournament in 1989, when he took third at 118 lbs. The latter went on to eventually win three Midlands titles.     Tsirtsis, who carries a high school record of 195-0, has attended several Midlands events in the past, and he will be competing against what he knows will be "the best in college wrestling."     "I always set my goals pretty high," said Tsirtsis. "I don't feel pressure to follow in the footsteps of Carr or Kolat, but I will still go out there with the same mentality."     Added Tsirtsis' mother, Dawn: "He is very excited for this, and has been working extra hard for this all season. He knows (wrestling in Midlands) will be a challenge. He is trying to prepare himself as best he can."