ST. ANDREWS, Scotland—Three more players withdrew from the British Open next week at Royal St. George’s, a growing list that includes Masters champion Hideki Matsuyama, who was concerned about practice time and travel. Two-time Masters champion Bubba Watson and former British Open champion David Duval also withdrew Sunday. That brings to 13 the number of players who had been planning to play but withdrew. Matsuyama tested positive for the coronavirus during the Rocket Mortgage Classic last week in Detroit and has been self-isolating. He remains symptom-free, though subsequent tests have come back positive. “I’m feeling fine but haven’t been able to practice in preparation for the Open,” Matsuyama said in a statement released by the R&A. “Combining that with the difficult travel to the U.K., my team and I have decided it’s best to withdraw to ensure everyone’s safety.” Watson had to withdraw after he said he was in close …