Brandon Allen certainly sent a message that he’s up for the challenge of competing for the A’s first baseman job this spring by belting a grand slam and driving in seven runs in a 12-10 victory against the Chicago Cubs on Sunday.

Allen went deep in the fourth, added a two-run double in the fifth and drove in the go-ahead run in the ninth with a groundout. In 41 games with the A’s last year, Allen hit .205 with three home runs and 11 RBIs.

Eric Sogard also went deep for the A’s, his second of the spring.

Opening Day starter Brandon McCarthy struggled in three innings of work, giving up three runs, two of which were earned, and four hits. Travis Schlichting picked up the win in relief.

Former A’s prospect Adrian Cardenas drove in three runs for the Cubs.