The St. Louis Cardinals (86-47) are the best team in the MLB, but the Pittsburgh Pirates (79-53) aren't too far off as they boast the second-best record in the National League. Pittsburgh hopes to rebound after the last time they visited their division rivals.

Scroll to the bottom for the MLB live stream and radio broadcast for the matchup between the Cardinals and Pirates at 8:15 p.m. ET.

St. Louis welcomes back outfielder Jon Jay, who was activated from the disabled list on Friday after missing two months with a wrist injury. The Cards will send right-hander Carlos Martinez (13-6, 2.91 ERA) to the mound to face Pirates' left-hander J.A. Happ (7-7, 4.10 ERA).

Martinez, 23, was tattooed by the Pirates the first time he faced them back in May, but he has rebounded in his last two outings against the division rivals, going 2-0 with a 1.76 ERA. The youngster got the Cardinals off to a good start in the last series between these two back in mid-August and pitched eight innings of three-run ball while striking out eight.

However, Martinez will face a tougher task this time around because the Pirates are playing with their backs against the wall. Pittsburgh will face St. Louis only six more times this season and if the Buccos hope to sneak away with an NL Central title, they'll need to take advantage of all of these matchups as they trail the Cardinals by 6.5 games in the division.

Pittsburgh really shot themselves in the foot this week after dropping four in a row - including a three-game sweep at the hands of the Milwaukee Brewers - but it'll be a much different scenario when they arrive at Busch Stadium.

The Pirates acquired Happ before the non-waiver trade deadline and he's provided good depth for the starting rotation. The left-hander is 3-1 with a 1.98 ERA in five starts with Pittsburgh, but he'll face the toughest test with his new team on the road tonight against the Cardinals.

Happ is just 1-8 with a 6.79 ERA and 1.57 WHIP in 10 career starts vs. St. Louis.

The Associated Press also noted the Pirates have not won a series in St. Louis since April of 2013 and are 4-18 at Busch Stadium since then, so Happ is going to need all the help he can get from the Pirates' offense.

St. Louis hopes outfielders Jason Heyward and Stephen Piscotty can continue producing runs as the team copes with multiple injuries while the Pirates desperately need an all-around effort tonight to keep the division race close.

Check out the lineups for each team here.

Click here to view the live stream for tonight's game (as well as the rest of the series) or check out the live radio broadcast here (STL) or here (PIT).