The MLB season grind hits its height after the All-Star break. While the toll it takes on position players may be more evident when watching a game, numbers show how much pitchers tend to struggle in the second half. Although the League’s ERA differential between pre- and post-All-Star break has been inconsistent over the past five years, it’s hard to forget the catastrophic collapse of Ubaldo Jimenez that sent his career spiraling.

When looking at some of the game’s best pitchers, it’s evident that several starters thrive in the first part of the season, but when it comes to the second half, things aren't as favorable. In looking at this split, it’s time to see which big time starters are likely to perform as well as they did in the first half of the season or not.

Please be Good, Johnny

With the exception of last season, Johnny Cueto has never had a better second half than first half. One could argue that last year’s second half was worse than his first because he only threw in two games due to injury. That’s not to say Cueto has always pitched poorly in the second half of the season, he just never pitches better than he does in the first one.

Cueto has a career 3.03 ERA in the first half of the season, whereas his ERA jumps by almost a run (3.92) in all post-All-Star games of his career. In 2012, he didn’t have a bad second half, but his ERA jumped from 2.39 to 3.26 in the second half of the season. The righty also saw his WHIP take a slight jump, but nothing major.

Cueto saw similar jumps in the previous two seasons, but his big flop was in 2009 where his ERA went up by over two runs in the second half of the season. Cueto has made adjustments for the latter part of each season throughout his career, but has consistently displayed that his numbers will get slightly worse when the second half kicks off.

Win Wright?

Adam Wainwright has lit up the NL with success yet again this year. He's tied for the MLB lead in complete games, and tied for second in shutouts. The Cardinals' ace also is tied for the league lead in wins and sits atop the league in ERA, with the only ERA among starters still below 2.00, besides another pitcher mentioned later in the article. It remains to be seen if he can maintain his awesome start.

In the past few years, Wainwright has been up and down with his performances between his first and second halves. Last season he had a jump in his ERA by a run, but in 2012 it was the opposite. The 6’7” starter logged a 4.56 before the break, but then figured out, earning a 3.28 ERA and had noticeably better WHIP, too.

It will be hard for Wainwright to maintain the numbers he had in the first half, but it's safe to assume he'll post good numbers. Lastly, with a FIP of 2.52, it’s a smart bet to say his ERA will bump up, even though he will have continued success.

Figurehead of the Seattle Monarchy

The Mariner ace never fails to stand up to his title as King. Felix Hernandez has made 20 starts already this season, and continues to dominate. His rock-solid 2.12 ERA has helped him to his 11-2 start thus far. He's managed to throw 144.1 innings, too, and limited hitters to 105 knocks posting a 0.90 WHIP going into the break, in addition to his league leading 2.04 FIP.

Over two of the past three seasons, Hernandez has thrown better in the second half than the first half. Last year was most noticeable when he had a 3.45 ERA in the first half, but then had a 2.63 for the rest of the way. Going based off recent history and, more importantly, his FIP, Hernandez is going to keep up the good work once his next outing comes around.

Stupid Good

The two-time Cy Young winner has had an electric first half, with his career first no-hitter topping everything off, in addition to his 41-inning scoreless streak. Clayton Kershaw leads the league with his 1.78 ERA, 1.60 FIP and 0.83 WHIP. Clearly he has most MLB hitters figured out and is dicing everyone up, striking out 126 over 96.1 innings, for a 11.8 K/9.

Last year was clearly Kershaw’s best year, and his second half was even better than his first. In both the halves of the season, his ERA was under 2.00, and he kept his WHIP below 1.00 before and after the break. The Texas native had his best half of any season in 2011, where he logged a 12-1 record with a 1.31 ERA and a 0.89 ERA - after the All-Star game. Kershaw has shown that fatigue won’t stop him during the year, and he hasn’t given inclination that he is ready to give up the title of “best pitcher in baseball,” yet.

The Remaining Windy-City Ace

Chris Sale is now in his third season as a starter at the MLB level, and continues to grow as a pitcher. Sale’s 2.08 ERA and 0.42 WHIP lead the AL, and while his FIP (2.47) is a little higher than his ERA, it is not far off.

Though this is definitely his best start in any season in his career, the Chi-town ace has been a first half pitcher. He has had a sub-3.00 ERA in the first half since 2012, but his second half numbers have not been as good.

Sale has managed to maintain a consistent K/9 throughout his time as a starter, regardless where he is in the season, but the same cannot be said of his WHIP, which is slightly worse in the second half. Sale’s ability to stay healthy will be put to the test, but it’s certain that he will see his numbers fall in the second half.