ST. PETERSBURG -- Unbeaten at home and firing on all cylinders after a 4-1 win over the White Sox on Sunday afternoon, the Rays are ready for another big test at Tropicana Field. 

Here come the defending champion Astros, with a three-game series starting Monday night.

“We know the great team that Houston is, and what they bring to the table when they come in here,” third baseman Isaac Paredes said through communications manager Elvis Martinez. “They're going to come in and try to prove a point against us since we're playing really well.

“But also, I know who's in this room, and I know what my guys bring to the table as well, and it's going to be a good series.”

Houston gave Tampa Bay a tough time down the stretch last season, winning five of six games by a combined score of 22-11. But this isn’t last year -- certainly not with the way the Rays are rolling right now.

Sunday’s fifth consecutive victory, before a home crowd of 22,702, completed the Rays’ fifth series sweep of the season and improved their record to 19-3. It’s the best 22-game start to a season in the Majors since 1987, when the Brewers were also 19-3. Only two teams in MLB’s modern era, the 1911 Tigers and '55 Brooklyn Dodgers, won more of their first 22 games.

Much of the Rays’ success has come under their own roof, as they are a perfect 13-0 at Tropicana Field -- the longest home winning streak in franchise history. This season-opening stretch at home matches the 2009 Dodgers for the longest such streak in the live ball era and trails only the 1880 Chicago White Stockings (21 straight), '86 Detroit Wolverines and '84 St. Louis Maroons (16) and '85 White Stockings (14) in AL/NL history.

Their latest win was the product of a familiar formula.

Starter Zach Eflin led the way in his return from the injured list, cruising through five innings while allowing just one run. The Rays were hoping to have him pitch four innings in his first start back, manager Kevin Cash said, but Eflin went back out for a fifth after he'd thrown only 60 pitches.

“I pray before every inning on the back of the mound, ‘Please get me out of this inning with as few pitches as possible,’” Eflin said. “That's my number one goal. I always try to be efficient.”

He was at his most economical in the fifth, retiring the bottom of the White Sox lineup on seven pitches and putting himself in position to earn his third win.

“It kind of worked out perfectly,” Cash said. “When you kind of get the opportunity to get a win or leave with a win, you want to give it to him.”

The Rays played crisp defense behind Eflin, especially with Paredes putting on what Cash called a “clinic” at third base all day. And Eflin received some early run support from Luke Raley, who snapped out of a recent 4-for-32 skid by crushing a Statcast-projected 442-foot two-run shot to right field off Lucas Giolito during the Rays’ three-run second inning.

“They’re really, really hot, so when you’re going up against a team of that caliber, you’ve got to be executing a lot,” said Giolito, who lost to the Rays for the first time in seven career matchups. “Unfortunately, I just didn’t get the job done.”

Tampa Bay has homered in all 22 games so far this season, but it was Raley’s first long ball since he hit three in two days on April 3-4. While the Rays hadn’t lost any faith in him, Raley’s relief was evident afterward.

“It's really easy to press, especially when it seems like everybody else on the team is hitting the crap out of the ball,” Raley said. “That also makes it easier to struggle and know that people are going to pick you up behind you. It's really nice, and it's a fun team to be on.”

Harold Ramírez padded the Rays’ lead in the third with his fifth home run, one shy of his total from last season. After Eflin allowed one run on a pair of doubles in the fourth inning, he teamed up with Yonny Chirinos (three innings) and Pete Fairbanks (third save) to retire the last 17 hitters they faced in order.

“The offense has had our back the entire season, and it doesn't show like they're letting up,” Eflin said. “So it's been a lot of fun.”