Australia batsman Shaun Marsh is eager to take his opportunity in the Ashes, unwilling to think another failure could end his Test career.

Marsh was a surprise selection for the first two Tests against England, with the left-hander expected to bat at number six.

The 34-year-old averages just 36 in Tests, while he has scored 236 runs at 39.33 for Western Australia this Sheffield Shield season.

Further failures could mark the end of his career in the format, but Marsh is simply keen to seize his chance when the Ashes opener begins in Brisbane next week.

"I'm trying not to think about it that way," he told a news conference on Saturday.

"It's just another opportunity for me now to get out there and play some good cricket for Australia and I know I've got some runs in me still to go.

"I've just got to prepare well, just enjoy it and have a lot of fun and back myself in."

No Australian batsman managed to stake a strong claim for the number six spot, with Marsh's state team-mate Cameron Bancroft (442 Shield runs at 110.5 this season) to open after his impressive start to the season.

Marsh said he had avoided thinking about possible Ashes selection, preferring to focus on his performances to earn a spot.

"I didn't put a lot of thought into it over the last three or four months, I just tried to play some good cricket for WA and if I did that I thought I might be a sniff," he said.

"I guess to get that call was a lot of excitement and I just can't wait now to prepare well and get out there and have a crack."