Christian Yelich’s injury is a gut punch to the National League Wild Card race. Just when it seemed the Brewers might grab the second berth from the Cubs, their best player’s broken right kneecap forces us to take another look at things.

The Brewers still should not be counted out. They’re tied with the Cubs (Milwaukee would have home field in a potential Wild Card tiebreaker game based on its 10-9 record vs. Chicago this season), have a more favorable schedule and have cleared an array of other hurdles to get to this point.

Also, good teams come to believe they can overcome virtually anything. But to lose one of baseball’s two or three best players is a devastating blow both to the Brewers and to MLB, because Yelich has come to represent everything we want from professional athletes.

Back to the races. With 17 days remaining in the regular season, 15 of 30 teams are still in contention. Some of them have all but wrapped up berths, and some are clinging to the slimmest of hopes.

And then there are the Rays, A’s and Indians in the American League -- three teams fighting for two Wild Card spots. In the NL, the Nationals hold the top Wild Card position by 3 1/2 games.

And that’s where it gets interesting. The Cubs and Brewers are tied for the second spot, they're two in front of the Mets and Phillies and 3 1/2 in front of the D-backs.

Here are seven things that could decide the four Wild Card teams:

1) Trent Grisham, potential folk hero
The Brewers aren’t going to replicate Yelich’s production. Not with one guy or any combination of guys. So they must get production from the people you’ve heard of: Lorenzo Cain, Mike Moustakas, Ryan Braun. And then there’s the 22-year-old Grisham, a first-round Draft pick in 2015 with 33 Major League games under his belt. He suddenly has a more prominent role than he could have imagined. His .257/.316/.467 line through 117 plate appearances is a promising start, as is the fact that in his first at-bat on Wednesday as Yelich’s “replacement," he hit a home run off Pablo Lopez of the Marlins.

2) The Cubs finish on the road (gulp!)
The Cubs leave Wrigley Field for the final time on Sept. 22 to finish the regular season with three games in Pittsburgh and three in St. Louis. That matters because Chicago has been a very good home team: 47-24. On the road, the Cubs are 31-44, and no amount of Jedi mind tricks (home uniforms hanging in road-clubhouse lockers) from manager Joe Maddon has changed things.

3) AL schedule favors the Rays and A’s
The A’s wrapped their series against the Astros on Thursday night at Minute Maid Park, and now finish the regular season with 15 games against teams with losing records. The Rays have four games against contenders -- two against a Dodgers team that has already clinched the NL West, and two against the Yankees, who probably will have clinched the AL East by the Sept. 24-25 series. As for the Indians, they’ve got nine games left against contenders -- three apiece against the Twins, Phillies and Nationals.

4) Austin Meadows is healthy and raking
The Rays have won 11 of 13 with a mighty bullpen -- and a closer, Emilio Pagán, who may be baseball’s best. Meanwhile, Tampa Bay’s offense has caught fire at the right time. Meadows, the 24-year-old outfielder, was hitting .472 this month at the start of play on Thursday. He appears poised to enter the national spotlight, especially if the Rays can hold on to a Wild Card spot.

5) Mad Max, Doolittle and a brutal schedule
The Nationals could pay a big price for their 19-31 start. Having since positioned themselves to return to the playoffs, they now play 15 of their final 18 games against contenders (Twins, Braves, Cardinals, Phillies, Indians). Two positive signs are the return of Max Scherzer -- fresh off his best performance in two months -- and former closer Sean Doolittle, who has made three scoreless appearances since returning from the injured list. Both will need to be at their best while toeing the fine line between “let’s try to make sure to get home-field advantage in the Wild Card Game with Scherzer rested” and “let’s try to make sure we are healthy for October without blowing it.”

6) Harper on the spot
In his first game back at Nationals Park in April, Bryce Harper did a completely Bryce Harper thing: He hit a moonshot home run into the right-field seats in the sixth inning. What could ever top that moment of drama? The Baseball Gods may be about to deliver the perfect finishing touch: Five -- yes, five -- Phils-Nats games at Nationals Park in the final week of the season. If we’re lucky, both teams still will be in contention, and, well, you can figure out the rest.

7) The Reds and Red Sox could cause chaos
The Red Sox aren’t going to repeat as champions, but they could help determine who gets to play in this year’s World Series. They’ve got six road games -- two in Philadelphia this weekend and four against Tampa Bay at Tropicana Field next weekend -- that will help decide playoff berths. The Reds play 12 of their final 16 games against teams still in contention (three apiece against the D-backs, Cubs, Mets and Brewers).