Only one first-round series is still undecided, with Nashville and Anaheim meeting in Game 7 tonight. Thus far, WhatIfSports.com's NHL predictions have been a mixed bag. We successfully picked the Capitals, Lightning and Stars to advance, but missed on the Penguins, Islanders, Blues and Sharks. We'll be rooting for the Ducks this evening to salvage a .500 record in Round 1.

Looking ahead to Round 2, we played each matchup 1,001 times using our NHL simulation engine to determine which team has the upper hand. We'll be updating our second-round predictions after the Nashville-Anaheim series is decided.

Stanley Cup Playoffs: Second-Round Predictions

Matchup Win % Avg. Score
Lightning 51.0 2.2
Islanders 49.0 2.1 Simulate Game
Capitals 66.3 2.6
Penguins 33.7 1.8 Simulate Game
Stars 55.9 2.7
Blues 44.1 2.4 Simulate Game

The Capitals, our pre-playoff pick to win the Stanley Cup, are heavy favorites over Pittsburgh in the second round. Washington won 66.3 percent of simulations, outscoring the Penguins by an average of 2.6-1.8. In 1,001 simulations of the entire playoffs before the postseason began, the Capitals won the Cup 35.5 percent of the time, while the Penguins won just 1.0 percent of the time.

The predictions don't get much closer than Islanders vs. Lightning. Tampa Bay won 51.0 percent of head-to-head matchups, edging New York in goals by an average margin of 0.1. The trend holds with pre-playoff predictions, when the Lightning were given a 4.9 percent chance to win the Stanley Cup, compared to a 0.7 percent chance for the Islanders.

In the Dallas vs. St. Louis series, our NHL prediction engine gives the nod to the Stars, with the team winning 55.9 percent of simulations by an average score of 2.7-2.4. Our original predictions gave Dallas a 12.2 percent chance of reaching the Stanley Cup Final and 2.8 percent odds to win the Cup. St. Louis had just a 3.4 percent chance to play in the Stanley Cup Final and a 0.3 percent chance to win it all.

As for tonight's Game 7, we played the Predators vs. Ducks 1,001 times at the Honda Center. Check out the results:

Ducks vs. Predators: Game 7 Prediction

Matchup Win % Avg. Score
Predators 36.9 2.3
@ Ducks 63.1 2.9 Simulate Game

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