Baltimore Orioles’ Adam Jones, left, doubles in front of Minnesota Twins catcher Kurt Suzuki in the fifth inning of an opening day baseball game in Baltimore, Monday, April 4, 2016. Manny Machado and Joey Rickard scored on the play. (AP Photo/Patrick Semansky)

The Baltimore Orioles are off on an explosive start to the 2016 season, building a 4-0 record after a series sweep of the Minnesota Twins and a single victory over the Tampa Rays.

Baltimore beat Minnesota in a three-game series played April 4 to April 7, and then dominated Tampa in the first of a three-game set on April 8.

Entering this season, most baseball pundits believed the Orioles’ only hope of winning games would be to out-slug their opponents in high-scoring affairs. The team paid more attention this offseason to bolstering the hitting lineup, rather than improving a weak pitching rotation. Re-signing home run king Chris Davis and adding power hitter Mark Trumbo in free agency strengthened Baltimore’s offense, but what about the Orioles’ defense?

Baltimore Orioles starting pitcher Yovani Gallardo throws to the Minnesota Twins during a baseball game in Baltimore, Wednesday, April 6, 2016. (AP Photo/Patrick Semansky)

Baltimore Orioles starting pitcher Yovani Gallardo throws to the Minnesota Twins during a baseball game in Baltimore, Wednesday, April 6, 2016. (AP Photo/Patrick Semansky)

So far, Baltimore has been surprisingly sharp in the field, allowing no more than two runs in any of their first four contests. The pitching staff has been solid, despite worries that it wasn’t properly shored up via free agency. Yovani Gallardo, the one starting pitcher Baltimore did bring in this offseason, had a strong outing in his Orioles debut on April 6. The former Brewers All-Star pitcher gave up just two hits and one run with four strikeouts in five innings pitched on April 6, helping lead the O’s to a 4-2 win. Ubaldo Jimenez was just as sharp on the mound on April 7, striking out nine batters through seven innings.

But the bullpen has been just as impressive as the starting pitching. Relief pitchers Tyler Wilson, Brad Brach, Daren O’Day, T.J. McFarland and Zack Britton have all put in serviceable innings throughout the first week of the season, and they have yet to surrender a run.

If the Orioles can keep up the quality pitching, they may be the pleasant surprise of the league this season. It’s already clear that the team can generate runs on offense—that was evident on April 8 when Baltimore recorded four home runs in a 6-1 win against Tampa ace pitcher Chris Archer. A powerful hitting lineup can make Baltimore a good team, but if they can somehow combine that with strong pitching, they’ll go from being a good team to become a great one.