Additon pitched seven one-hit innings but gave up two more early runs on Friday night as the Memphis Redbirds were blanked by the visiting Round Rock Express, 3-0.
Through 11 Triple-A outings, the Cardinals prospect has compiled a 6.18 ERA in innings one through four and a 3.50 mark in innings five through seven.
"It's definitely something I need to address. This past month, I have struggled in the first couple of innings," Additon said. "[Friday], I started off a little shaky, but I got stronger as I was going."
In fact, the 24-year-old left-hander retired the final 10 batters he faced, but it was too little, too late. Additon gave up a pair second-inning runs after allowing just one hit: Veteran Brad Nelson singled to center field.
"He hit a fastball that was supposed to be a fastball in and ran out over the plate. He hit it up the middle," Additon said. "That was the inning that unraveled for me."
Additon walked in a run and allowed another on Dusty Brown's sacrifice fly. He issued three free passes in the frame and five for the game while striking out four.
The result? Another defeat.
Additon (1-6) has lost three straight starts and his early-game woes have pushed his ERA to 5.40.
To address his problems, he said he's working on two physical adjustments, one to achieve greater balance on the mound, another to better control his fastball. In pursuit of the latter, Additon has started spreading his index and middle fingers on his grip.
He's not yet seeing the success he'd like, but he appears confident it's on the way.
"When I throw the ball well," Additon said, "I get good results. I am trying to be more consistent."
Express counterpart Greg Reynolds (4-4) was just that, holding down the Redbirds for seven innings. The 2006 first-round Draft pick yielded six hits and walked four but did not allow a run.
"He definitely outpitched me," Additon said.
Nelson's single extended his hitting streak to eight games. He's also hit safely in 21 straight road games, the Pacific Coast League's longest such stretch this season.