We're one week into the 2013 season, and the best teams in baseball have already emerged and risen to the top of the standings.

Or have they?

Raise your hand if you expected the Braves, D-backs and Rockies to boast 5-1 records after six games. Who expected the Yankees and the Blue Jays to both be 2-4?

That's right, it didn't take long for America's pastime to remind its fans that they should expect the unexpected. Anything can happen in the regular season, and predictions -- like Spring Training records -- are often forgotten.

But here's what we do know: The Nats are for real, and the words "sophomore slump" and "Bryce Harper" probably won't be used in the same sentence very often. As expected, the Rangers, Angels, A's and possibly the Mariners will all beat up on each other in the American League West, and how the teams fare against the Astros could decide which team or teams make it to the playoffs.

Remember how good Cincinnati was last year? We do, too. This season's offense machine is already showing off its power, and that's not good news for everyone else in the National League.

Speaking of the NL, you don't have to be a Braves fan to love what brothers B.J. and Justin Upton are doing in Atlanta.

The Giants have won the World Series twice in the last three years but do they have enough power to do it again?

It's time to hear your voice and your vote.

MLB.com has set up a panel of experts to vote on the top 15 teams each week. The group includes MLB.com vice president and executive editor Carlton Thompson, VP and executive producer Jim Jenks, columnists Mike Bauman, Hal Bodley, Anthony Castrovince, Richard Justice, Matthew Leach, Terence Moore and Tracy Ringolsby, reporters Barry M. Bloom, Marty Noble, Jesse Sanchez and Lyle Spencer, and MLB Network analyst Mitch Williams.

Agree? Disagree? The power to rank the teams is yours.

This Week's Power Rankings
This Week Movement Power Player Last Week
1

The Nationals were outscored, 27-10, by the Reds over the weekend, but there are still plenty of reasons to be optimistic if you are a Washington fan. First of all, Harper has a hit in five of the Nats' first six games and is hitting .360 in that span. He already has four two-hit games and has scored five runs.

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2

Want offense? Todd Frazier was hitting .480, Shin-Soo Choo was hitting .375, Xavier Paul was at the .375 mark and Brandon Phillips upped his average to .333 through the first week of the season. The Reds scored 38 runs, the second most in baseball, and hit 11 home runs. Only the Rockies (13) and the A's (12) had hit more.

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3

The Braves are coming off a three-game sweep of the Cubs, and they've lived up to their reputation as heavy hitters in the NL East. Atlanta hit 11 home runs the first week, and Justin Upton hit five of them.

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4

Josh Hamilton was off to a slow start, but he had three hits Sunday against the Rangers and could be snapping out of his early-season funk. Don't be fooled by Albert Pujols' statistics. The slugger had only four hits through the first week, but three of them came in his past two games. He was walked eight times and had two home runs through the Halos' first six games.

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5

The defending World Series champions were 3-3 after the first week and are coming off a series loss to the Cardinals, but nobody is panicking in San Francisco. That said, the Giants need better execution with runners in scoring position. The Giants combined to hit just .172 (5-for-29) with RISP in their first six games.

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6

The hot-hitting Tigers scored eight runs in each of their first two games against the Yankees, including 17 hits on Saturday, but they fell short of the three-game sweep with a loss on Sunday. Miguel Cabrera and Prince Fielder combined for 14 RBIs and two home runs through the first week.

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7

Yu Darvish was almost perfect in his first start and the rest of the Texas pitching staff also pitched well. Nelson Cruz, Lance Berkman, Ian Kinsler and A.J. Pierzynski have provided most of the offense's firepower this season, while Elvis Andrus and Adrian Beltre are starting to look comfortable at the plate.

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8

The good news for Dodgers fans is that Adrian Gonzalez drove in four runs and picked up three hits on Sunday, and the offense is starting to click. The not-so-good news? Matt Kemp had two hits in 20 at-bats and drove in only two runs the first week. But here's the great news: Clayton Kershaw won his first two starts and is already pitching like the best pitcher in the NL.

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9

The A's won five in a row to race to the top of the standings in the AL West. Jed Lowrie was hitting .500 with three home runs and six RBIs, and things could get even better in Oakland. Josh Reddick, who is day to day with a sprained his right wrist, could be back in the lineup soon, and it's only a matter of time before Yoenis Cespedes, who has scuffled at the plate, finds his groove.

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10

The new-look D-backs went 5-1 the first week, in large part because they no longer rely on the home run to score most of their runs. This year's squad is getting hits with two strikes, sustaining rallies and being aggressive on the bases while still launching an occasional long ball.

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11

Jose Bautista missed three games because of a twisted right ankle, but he is expected back in the lineup against the Tigers on Tuesday, possibly as the designated hitter, and his presence will help. R.A. Dickey, the club's no. 1 starter, came up short in his first two outings of the season, but few expect the reigning NL Cy Young Award winner to struggle for long.

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12

David Price, the reigning AL CY Young Award winner, was hit hard in his last outing, giving up eight runs on 10 hits in five innings against the Indians. But the staff ace is not worried, saying it usually takes him a few starts to feel comfortable on the mound. Ben Zobrist has paced the offense, hitting .429 with two home runs, and Evan Longoria has already found his All-Star form, with seven hits in the first six games.

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13

The Cards rebounded from a tough Opening Series loss to the D-backs to win two of three against the Giants in San Francisco. Pete Kozma has been a sparkplug for the offense, but the club could use better performances at the plate from Carlos Beltran and Yadier Molina, who were hitting .235 and .240, respectively, through the first week. Overall, the team's batting average is .261. What's more, the club hit only four home runs.

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14

The Red Sox won two of three games from the Blue Jays in Toronto, and they can thank Will Middlebrooks for their good fortune. The third baseman had four hits, including three home runs, in the series finale on Sunday and was hitting .320 for the season. Jose Iglesias is red hot at the plate, with a .529 batting average and multiple hits in four of the five games played this season.

15

Don't look now, but the Rockies were 5-1 after the first six games of the season, slugging their way to the top of the NL West standings. Colorado won its first two series of the season for the first time since 1995.