This inquiry explores the effect of a wider construct definition of linguistic knowledge —which covers a phraseological component—in accounting for variance in reading performances. Test scores of 418 learners of English as a foreign language (EFL) were modeled in a structural equation model, displaying that a phraseological knowledge measure outperformed traditional syntactic and vocabulary measures in forecasting reading comprehension variance. Additional insights into the role of phraseological knowledge were gained via verbal protocol analysis of 15 EFL learners answering reading comprehension items that targeted the understanding of phrasal expressions within written context. The outcomes hint at an underestimated, but critical, role of phraseological knowledge in FL reading, and are pertinent to both the evaluation and the teaching of EFL ability.