This mixed methods correlational study investigates the relationship between EAP/ EFL learners' written performance and writing anxiety. Although it is sometimes overlooked in pedagogical planning in large classrooms as in KSA, situational writing anxiety can significantly narrow the scope for learners to write communicatively. The study participants comprised a convenience sample of 120 upper-intermediate students enrolled in three academic EAP courses in the EFL department at Majmaah University. An edited version of Horwitz’s Foreign Language Classroom Anxiety Scale (FLCAS) was used to gauge the participants' anxiety levels in three iterations of writing tasks. These findings were fortified with the results of the thematic analysis of focus groups conducted with fifteen volunteering learners. Results indicated that cognitive and affective writing anxiety facets like fear of negative judgments or time pressure were the primary originators of learners’ anxiety in the writing class. However, the average scores for anxiety showed a slight but not statistically significant drop across the three attempts. This finding was correlated with learners’ feedback in the focus group discussions which highlighted the fact that being aware of anxiety helped learners feel less anxious as experience reinforced that such anxiety was uncalled for. Learners’ anxiety perceptions were modified due to teacher feedback and the assurance that their peers had the same obstacles as themselves, a fact that would keep peer criticism at bay. The theoretical basis for this study comes from Krashen's Affective Filter Hypothesis and Horwitz's foreign language anxiety model. Pedagogical gains can be expected from the key finding that writing anxiety is highly correlated with learners’ performance, teachers can be guided in making appropriate changes. The study concludes with pertinent recommendations, mainly that Saudi writing classrooms need newer strategies to support learning such as keeping the writing tasks simpler, providing adequate and optimal practice, and having scaffolding measures in place. The study underscores the value of understanding and overcoming emotional obstacles to effective writing in EFL learning.