Good outing or bad one, though, he tells it like it is. His words may be few between his starts, but every five days this 22-year-old kid is just as honest with himself as he is with media.
He was less than thrilled with his season debut Friday, when he surrendered six earned runs in five-plus amped-up frames at Toronto. His sinker wasn't there, and neither was his command, leaving him more than disappointed.
On Wednesday, though, in a 4-1 win over Texas, Cahill flashed a calming postgame presence to go along with equally impressive in-game pitch selection and command.
"The biggest thing was I made pitches when I had to," Cahill said. "I mixed it up pretty good this time. I think that was the biggest difference. Last game when I had to make a pitch it seemed like they hit a home run. Today I was able to get some double plays in big situations, so that helped out."
Cahill, who offered up an Oakland rookie-record 27 long balls last season, gave up three to the Blue Jays. On Wednesday, he didn't let a single ball leave the yard and, instead, garnered two double plays.
"He's thrown that same game right there several times," said Landon Powell, who also caught Cahill's last start. "He's got a good, hard sinker and can attack you with his fastball and his changeup. He's got a pretty good slider-curveball combo, too. I think he just went out and attacked the zone. He had good stuff and they had a hard time squaring it up."
Overall, the right-hander allowed just two Rangers runners past first base as he notched his first season win while lowering his career ERA against Texas to 2.05 -- his best mark against any American League team. Only Los Angeles' Scott Kazmir (1.96) trumps Cahill's career stats vs. Texas for pitchers with at least 17 innings.
"He's got good stuff," Rangers manager Ron Washington said. "When he's on, he's good. He had a good slider today and a sinker.
"The A's have good pitching. It may not be as consistent yet as they'd like, but on any given day they can shut you down."
Cahill did just that, notching three 1-2-3 frames while throwing 90 pitches, 56 of which resulted in strikes. He left with runners on first and third in the sixth and, though he insisted he could have finished the frame, he understood his manager's reasoning for handing a 3-1 game to the bullpen.
"I haven't really gone over the 85-pitch mark, and our bullpen is the strongest part of our team right now," he said, "so there's no point in risking anything, especially with an off-day tomorrow."
"We wanted to keep him at 90-100 and, had he not gotten into any trouble right there, I certainly didn't want him to cough up the lead when he was certainly at the end of his rope," Geren said. "He had a couple of walks, but other than that I thought he kept the ball down. He had a real good changeup. His command was above average, so he gave us a chance to win."
Cahill not only received help on the defensive end but also offensively. The A's quickly gave him a 2-0 lead in the first thanks to a dose of small ball that scored Cliff Pennington and Daric Barton, who tallied a single and double, respectively. The A's then made it 3-0 in the fifth against Texas starter Colby Lewis courtesy of a solo homer off the bat of Eric Patterson.
Lewis was tagged for all three runs, along with five hits and three walks, through six innings of work for Texas. Reliever Darren Oliver lent the A's one final run in the seventh by surrendering an RBI single to Barton, who compiled a 2-for-3 day for the second straight game.
Meanwhile, Tyson Ross, Brad Ziegler and Andrew Bailey combined for four shutout innings to award Oakland's productive day at the plate. And in doing so, Bailey extended his scoreless-inning streak to a career-high 20 2/3 innings -- a mark that dates back to last year.
With the 2-1 series win, the A's once again gained sole possession of first place in the American League West standings, where they sat in second the last three days due to a 2-6 slump. Never mind it's early in the season -- this somewhat battered Oakland ballclub, which currently has eight players on the disabled list, knows every win is crucial.
"I think that's big in the clubhouse," Bailey said. "Everyone knows we have a young team. To be able to go out there and win a series against division rivals, that's going to hold strong for late in the season and give us that confidence that we need to contribute."
Jane Lee is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.