The calendar will flip from April to May this week, and it’s time for fantasy baseball owners to consider taking a deeper accounting of their rosters.

With that, here are five must-adds off your fantasy baseball waiver wire this week.

5. Mike Minor, SP, Texas Rangers

Last Saturday against the Seattle Mariners, Minor struck out a career-high 13 over seven innings with just one walk, one run and three hits allowed. Since a rough outing on Opening Day, he has a 1.75 ERA with a 36:10 K/BB ratio and 20 hits allowed over his last five starts (36 innings) while going at least six innings in all five. In three of his last four starts, he has induced at least 14 swinging strikes.

A slight tilt toward allowing fly balls might not play well pitching home games in Arlington as the season wears on, but Minor is also inducing ground balls at close to a 42 percent rate thus far.

There is danger of buying into a small sample size with Minor, but he has carried a solid second half of 2018 into 2019. He is just over the general line for inclusion on this list, but Minor would be higher if his ownership rates were lower.

ESPN Ownership: 55.3%
Yahoo! Ownership: 64%

4. Raimel Tapia, OF, Colorado Rockies

Tapia has cooled off a bit since hitting a home run in three straight games last week, but he’s still hitting .300/.352/.680 with three home runs, 10 RBI and 10 extra base hits over his last 18 games. With David Dahl now back healthy, Ian Desmond (.198, .588 OPS so far this season) should be the odd man out in the Rockies’ outfield shortly.

It would be better if Tapia consistently occupied a higher spot in the batting order, and there is a chance of regression looming. But in NL-only leagues he’s already useful, and he belongs on the radar as an add in deeper mixed leagues.

ESPN Ownership: 2.5%
Yahoo! Ownership: 5%

3. Yandy Diaz, 3B/1B, Tampa Bay Rays

With two RBI against the Red Sox on Sunday, Diaz has now driven in a run in five straight games with a 1.124 OPS over that span. Going back a little further, he has a .351/.413/.784 slash-line over his last 11 games and he is hitting .289 with seven home runs, 16 RBI and 18 runs scored in 25 games this season.

There’s nothing in Diaz’s previous major league resume, albeit over less than 300 plate appearances, to suggest he had his run through April in him. Some regression is sure to come, but he’s actually got a below average BABIP thus far (.288) and a .300 batting average seems within range. He’s also occupying premium spots in Tampa Bay’s batting order, hitting no lower than fifth all season and hitting leadoff, third or fourth in every game since April 12.

Diaz is also eligible at both corner infield spots in Yahoo! leagues right now, with eligibility at first base likely to come on other league hosts that aren’t already there.

ESPN Ownership: 41%
Yahoo! Ownership: 59%

2. Mike Soroka, SP, Atlanta Braves

In two starts for the Braves since being called up , Soroka has a 1.69 ERA with 13 strikeouts and five walks over 10.2 innings. Add in his two starts in Triple-A, and Soroka has a 23:6 K/BB ratio over 20 innings this season.

Soroka is scheduled to start Monday night against the San Diego Padres. Elevated pitch counts have helped limit his innings over his first two starts, including 109 pitches against the Reds last Wednesday, so coming off a shoulder injury last year it’s worth wondering if he’ll have some limits put on him in the short-term. But there’s no doubt Soroka belongs in the big leagues, and on mixed league fantasy rosters.

ESPN Ownership: 22.7%
Yahoo! Ownership: 46%

1. Michael Chavis, 3B/2B, Boston Red Sox

In eight games since being called up, Chavis has a 1.086 OPS with three home runs and nearly as many walks (six) as strikeouts (seven). In four of his last five games, he has an RBI and a run scored with all three of his home runs over that five-game stretch.He has also mostly played second base thus far (six starts), where the path to playing time is clearer, which adds to his fantasy value.

Chavis was on the fantasy radar as soon as he was called up, but as production has met that opportunity he’s now a worthy waiver wire addition in all leagues. Add in budding eligibility at two positions (he’s already got second base eligibility in Yahoo! leagues) and now is the time to get Chavis while you can.

ESPN Ownership: 8.6%
Yahoo! Ownership: 22%