Derek Norris in pink. That was A's starting pitcher Jarrod Parker's idea Tuesday night.

Parker asked the A's catcher to wear pink on his fingernails, the better to see Norris' signs behind the plate. The decision worked well for both men, Parker turning in a fourth consecutive strong game and Norris hitting a two-run homer as part of a 6-3 win over the Giants.

Norris has been coloring his nails for a couple of weeks now with the idea that it makes it easier for his pitchers to see the signs he puts down. He's used white and neon green, and he's looking for a bright purple. But he hadn't worn pink before Tuesday.

"Jarrod asked me to use pink," Norris said, holding up his right hand. "I guess it worked."

The change to color took place at about the same time the A's pitching staff took off on a nice run. Oakland has won 10 of its last 11 games with the pitchers posting a 2.39 ERA over that stretch, walking just 20 in 98 innings and striking out 73.

The color variety of the catcher's nails probably has less to do with it than pitchers such as Parker working their way out of early season funks. Tuesday saw Parker give up a tough-luck first-inning run, but the A's went ahead on Norris' homer in the second, then a two-run third inning gave Oakland a comfortable 4-1 lead over Giants rookie pitcher Mike Kickham.

"I didn't really do anything different after the first," Parker said.

When left fielder Yoenis Cespedes couldn't track down a catchable foul fly, the first inning saw Parker extended to 27 pitches, not to mention the run that should not have scored.

After the first, the Giants got just three base runners off Parker (3-5) for the remainder of his evening. He said his goal was to keep the subsequent innings to 13 or 14 pitches, the better to get deep into the game.

He succeeded, reaching seven innings for the third consecutive start.

"It's a combination of getting my mechanics down," Parker said. "Seven (innings) is pretty comfortable for me."

After getting off to a 1-5 start with a 7.34 ERA, Parker is 2-1 in his last four starts with a 2.96 ERA. In the process his overall ERA has come down almost two full points to 5.40.

Norris said the four consecutive strong starts were "very nice to see."