BALTIMORE — The Orioles keep knocking on the door, waiting for the old Brian Matusz to reappear, but continue to get no answer. And it’s growing more concerning with every start. On a night when the ball was flying out of Camden Yards with a combined nine home runs hit in the Reds’ 10-5 victory on Saturday night, Matusz looked more like the batting practice guy than the left-hander projected to be the No. 2 starter entering spring training. In just 4 2/3 innings against the Reds, Matusz gave up a season-high six earned runs, three home runs (tying a career-high), and nine hits while striking out five and walking one. His fastball touched 91 miles per hour once in the first inning, but consistently sat between 86 and 88 miles per hour for most of the evening. “The velocity obviously isn’t there,” said Matusz, who believes his changeup is getting better, but is still haunted by poor location. “Being in my fifth start, I feel like I’ve made a lot of progress, but I’ve just got to continue working and get a lot better.” In a sad contrast, Reds reliever Aroldis Chapman was hitting 101 on the stadium gun