Recent research has shown that knowledge of second language (L2) collocations is important to learners for improving their language processing and production but also that acquiring L2-specific collocations is a very burdensome task for learners. Thus, bootstrapping knowledge of L2 collocations through generalization is highly desirable, but this area has received surprisingly limited attention. This study examined L2 learners' ability to generalize knowledge of recently learned verb-noun collocations during processing and whether this type of learning occurred via intralexical associations in the L2 (similarity) or was facilitated by known collocations in learners' first language (L1). Mixed-effects regression targeting measures of learners' brain event-related potentials revealed cross-language influence during real-time processing that preceded learners' acceptability judgments. Both within- and cross-language similarity influenced learners' behavioral judgments. These findings revealed cross-language integration in L1-L2 incongruent collocations from the earliest moments of processing.