The Orioles reinforced that trust with a stellar performance against an American League East rival.
"That was fun to watch," Showalter said about Gausman. "That was impressive. I thought the seventh inning was the most impressive inning he had. You could tell he was going to carry good stuff. The secondary stuff was really good today. It was probably the best secondary stuff he's had this year."
Mark Trumbo also homered for Baltimore, which plays seven straight road games heading into the All-Star break. Tampa Bay still managed its first series win at Camden Yards in two years.
Gausman (5-7) appears to have put some of his early season struggles behind him. He did not allow a hit until Logan Morrison managed a two-out single in the fourth inning.
Gausman allowed just two hits with a season-tying high nine strikeouts and two walks. He has given up three runs in his past 18 innings, including another 5 1/3 shutout innings Tuesday against the Toronto Blue Jays.
"I think you only get confidence from success," Gausman said. "You got to have that first. Feel like I'm throwing the ball well right now and just got to keep it going. Like you said, I had a great second half last year, so obviously looking forward to that and knowing I'm the type of guy that gets better as the season goes on. That's always good."
Tampa Bay catcher Jesus Sucre ended the shutout bid with a solo homer in the eighth off Mychal Givens.
Rays manager Kevin Cash fractured his left ankle running near Camden Yards early Sunday morning but did not miss the game.
"I was crossing the railroad track and I looked up and stepped into the track, I rolled it," Cash said.
Tampa Bay starter Alex Cobb entered the game 4-1 with a 2.00 ERA in nine starts against the Orioles. This time, though, Baltimore took advantage of some miscues to open a 4-0 lead in the third.
Cobb (6-6) hit shortstop Ruben Tejada on the shoulder to put runners on first and second. After a sacrifice bunt by Joey Rickard advanced both players, Cobb had a throwing error on a grounder by Seth Smith that allowed the first run to score. Machado followed with a three-run shot to left.
"Any time you are on the mound, you are trying to win the ballgame," Cobb said. "There are some things you don't know what goes on to keep the game close. You don't have that big inning and you give your team a chance to win late in the game. But we're fortunate to walk out of here with two out of three.
"We need to win series and ultimately try to get to that 90-win mark and get into the playoffs."
Trumbo led off the fourth with a towering homer that boosted the lead to 5-0. A two-run double by Smith increased the lead to 7-0 in the seventh and ended the day for Cobb, who finished with six earned runs and six hits with three strikeouts and a walk.
The Rays simply could not respond against Gausman.
"That's about as well-pitched of a game that we've had against us this year or at least in a long time," Cash said. "Gausman was throwing 96, 98 miles per hour, spotting his fastball, showed a really good splitter and the occasional slider. I mean he made it really tough, so you're not going to piece together a lot of big innings when you're facing that kind of stuff and that type of command."
NOTES: Baltimore recalled RHP Jimmy Yacabonis from Triple-A Norfolk. To make room, RHP Alec Asher was optioned to the Tides. ... Rays SS Tim Beckham was back in the lineup after missing the previous game with a sore ankle. ... Baltimore RHP Chris Tillman will not travel with the team on Monday to Milwaukee because his wife is overdue with their first child. Tillman is scheduled to start Wednesday against the Brewers, but the Orioles have a contingency plan in place in case he cannot pitch.