Though it's hardly evident in his record, he's been even better in 2013.
Burnett looks for just his second win in the past three months Sunday as the Pirates try to maintain their grip on baseball's best record in this finale against the visiting Colorado Rockies.
The right-hander gave Pittsburgh its first 16-game winner since 1991 last season while posting the ninth-best ERA (3.51), fifth-best opponent batting average (.246) and fourth-best strikeout rate (8.01 per nine innings) during the Pirates' 20-year stretch of losing seasons.
Burnett (4-7, 2.86 ERA) has better numbers across the board this season, again ranking among the NL's top 10 in ERA and opponent batting average (.221) while posting the league's second-best strikeout rate (9.93). He just hasn't gotten much help.
Tuesday was the seventh time in Burnett's past 12 starts where the Pirates (66-44) scored exactly one run for him, though manager Clint Hurdle wasn't complaining about his pitcher's contributions in a 2-1, 11-inning win over St. Louis. Burnett seemed to be getting close to an ejection after arguing a call in the sixth, but escaped a jam and made it through seven, allowing three hits and a run while striking out nine.
"A.J. can get fired up. He's not one to hide his emotions by any means," Hurdle told the team's official website. "That's one of the things you love about him. He's out there and lets people know how he feels, including his teammates."
Pittsburgh has given Burnett just seven runs over his last six home starts, a total it nearly provided Francisco Liriano in seven innings Saturday. Jose Tabata homered, tripled and doubled in a 5-2 victory over the Rockies that was Liriano's seventh win in eight outings and extended the Pirates' NL Central lead over St. Louis back to 1 1/2 games.
Tabata had hit .116 in 43 at-bats over his previous 18 games with no extra-base hits.
For whatever reason, visits from Colorado bring out the best in him. Tabata has hit safely in all 11 career home games against the Rockies, homering three times in 45 at-bats and posting a .711 slugging percentage.
Tabata has five homers at PNC in 561 at-bats against all other opponents.
"We've seen Jose swing the bat like this before and be productive over the last few years,'' Hurdle said. "Hopefully, he will get hot.''
Burnett has faced Colorado (52-60) just once since 2004, though he's had the number of one Rockie from their time together in the AL. Michael Cuddyer is 3 for 24 with eight strikeouts against Burnett.
If Juan Nicasio (6-5, 4.92) pitches on Sunday anything like he did Tuesday in Atlanta, the Pirates should have little trouble supporting Burnett. The right-hander gave up a career-high eight runs over four innings in an 11-3 loss after posting a 0.47 ERA in three starts following a two-week stint in the minors.
"I'm feeling good, but it was a bad day,'' Nicasio said. "It was a bad game. I'm working hard for next time. I need to win. I need to win. I love the game. It's hard.''
Struggling on the road is nothing new for Nicasio. Opponents have an .865 OPS when he pitches outside of Denver, the fourth-worst mark for an NL starter.
Nicasio fared well, however, in his lone previous appearance at PNC Park. He held the Pirates to a run over 6 2-3 innings April 25, 2012, as the Rockies went on to win 2-1.
Colorado All-Star Carlos Gonzalez could return after being held out of the lineup the past four days with a sprained right middle finger.