Bumgarner threw seven more shutout innings, keeping pace with Arizona's Trevor Cahill, who took a shutout into the ninth inning against the Giants. Bumgarner finished April leading the Giants rotation in quality starts, ERA, WHIP, wins above replacement (WAR), walk rate and strikeout-to-walk ratio.
His 1.55 ERA is currently second in the National League. His 4.00 strikeout-to-walk ratio is the 11th best in the NL. If Bumgarner comes anywhere close to matching the pace he set in April throughout the rest of the year, he's going to contend for the Cy Young award.
His rotation-mates, Tim Lincecum and Barry Zito, have won Cy Young awards in their careers. Matt Cain has finished in the top 12 in the voting three times.
Cain took the ace moniker from Lincecum last season when he threw a perfect game and pitched all three clinching games during the team's postseason run. However, with a 6.49 ERA through six starts, Cain has dropped below Bumgarner in the pecking order early this season.
Being the ace of the staff goes beyond early-season statistics. There's a feeling on the days when Bumgarner pitches that the team is going to win the game no matter what.
It's the same feeling the Giants had last year when Cain took the ball every fifth day. It's also the same feeling that existed during the height of Lincecum's dominance when he won back-to-back Cy Young awards in 2008 and 2009, and closed the door on the Rangers in the clinching game of the 2010 World Series.
Timmy is defined in part by his competitive snarl on the hill. Cain is calm and stoic on the mound. Bumgarner has some of Cain's southern stoicism, but occasionally, his competitive flare will shine through.
Last year, Bumgarner was neck-and-neck with Cain as the ace of the staff through late August. After eight shutout innings against the Dodgers on Aug. 20, he was 14-7 with a 2.83 ERA. He was then hit hard in his final two August starts and blasted for a 5.47 ERA in September.
This year, there are reasons to believe that Bumgarner won't fade down the stretch like he did last season. Last year, right-handed batters put up a .694 OPS against Bumgarner, which was over 100 points higher than left-handed hitters (.581).
The reason for Bumgarner's platoon split and late-season fade could have been his over-reliance on the slider. His slider is an elite pitch with the same type of dominance as Lincecum's excellent changeup. However, the slider can be tough on the elbow, and it is best used against same-handed hitters.
So far this season, righties have put up just a .488 OPS against Bumgarner. The reason for his dominance against opposite-handed hitters seems to be the increased usage of his changeup.
The changeup has movement away from righties, which makes it a tough pitch for them to handle. According to FanGraphs, Bumgarner has decreased his slider usage by 5 percent over last season while increasing his changeup usage by the same amount.
Bumgarner is throwing his changeup more often, and the pitch looks better than it did last season. The changeup is also enhancing the effect of his slider and fastball, which are hard pitches with movement into right-handed batters. The changeup is a slower pitch with movement in the opposite direction.
Keith Law of ESPN poured some cold water on the simmering Bumgarner for Cy Young campaign by reminding his Twitter followers that Bumgarner had a similar start to last season before fading late. Keith is an excellent analyst, and it's always a good idea to avoid getting too excited over one month of quality performance.
However, Bumgarner's hot start seems to be more sustainable this year because of the increased usage and effectiveness of his changeup. Instead of being a two-pitch guy with a show-me changeup, he now has three excellent offerings to rely upon.
It's also not as though Bumgarner was chopped liver before April of this season. He finished 11th in the Cy Young voting two years ago and entered this season with a career 3.20 ERA over 534 innings.
Madison Bumgarner has always been a very good pitcher. It's just that he's appeared to have taken another leap forward so far this year. Instead of being a No. 2 starter, he's now the ace of the staff.
He's gone from being another guy in an outstanding rotation to the leader of the staff. If he keeps pitching like he did in April, the rest of the baseball world will soon take notice.