There's been a bit of shuffling of the top five teams in our weekly Power Rankings, with the Nationals making their debut as No. 1, and the Cubs, though surging, slipping a bit from their top spot. Three weeks into the season seems like a good time to give props to the Rockies and D-backs, who are thriving while the two teams normally leading the National League West -- the Giants and Dodgers -- are still trying to get on a roll.
Biggest jump: Welcome to the Top 10, Rockies. The Rox entered Tuesday in first place in the NL West, and considering they're doing this well with so many injuries to key players, it's fun to think about what they can do when they're at full strength. Since last week, Colorado has jumped a whopping 10 spots, from 16 to six.
Biggest drop: The Mets dropped four spots, from No. 10 to No. 14. Injuries are an issue; lack of power is a bigger problem. They're sorely lacking at the top of the lineup and are underwhelming throughout. Starting pitching has been fine, but that's little consolation for a club that has lost five of its past six, including a sweep by division-rival (and NL East leader) Washington.
Power Rankings Top 5:
1. Nationals (Last week: 3)
The Nationals are still trying to figure out the back end of their bullpen, but those early-season issues haven't done much to derail the first-place Nats. A variety of hitters are carrying the offense -- Bryce Harper, unsurprisingly, has gone above and beyond, winning NL Player of the Week recognition after hitting .550 with 10 runs scored, four doubles, three homers and seven RBIs over six games.
2. Astros (2)
If the Astros receive the kind of performances from Dallas Keuchel and Lance McCullers all season that they did in the first three weeks, they will be primed to run away with the American League West. There's a long way to the finish line, but given how productive the offense has been even with slow starts by star players Carlos Correa (.197) and George Springer (.216), Houston could be in for a big season.

3. Cubs (1)
The Cubs have been looking more like the Cubs lately, with clutch hitting and late-game comebacks contributing to the team's more recent fortunes. They fall from the top spot to No. 3 for the first time mainly because three weeks into the season, they've had more mediocre stretches than the Nationals and Astros. But the World Series champs are strong, and it's hard to envision them dropping out of the Top 5 this season.
4. Orioles (4)
After taking two of three vs. the Red Sox over the weekend, the Orioles have yet to lose a series. They aren't leading the AL in many of the major offensive and pitching categories, yet three weeks into the season, they have the second-highest win total. Baltimore has navigated around injuries to a couple of key pitchers, even more impressive given the offense has been mediocre in the early going.

5. Indians (8)
Slow starts are nothing new to the Indians, so it's highly unlikely there was a lot of panic in the clubhouse when they sputtered through a rather uninspired first couple of weeks. Cleveland won five of its past six games and led the AL with a 1.87 ERA during that stretch. The Tribe also ranked in the top five in the AL in batting average, slugging percentage and on-base percentage during that period.
The rest of the top 20
6. Rockies (16)
7. Yankees (7)
8. Red Sox (5)
9. Dodgers (6)
10. Tigers (9)
11. D-backs (11)
12. Rangers (15)
13. Marlins (12)
14. Mets (10)
15. Cardinals (18)
16. Pirates (13)
17. Rays (NR)
18. Mariners (17)
19. Reds (19)
20. Phillies (NR)