diff --git a/.travis.yml b/.travis.yml
index 2e0b68c3de..b7b17f2f19 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -16,6 +16,8 @@ matrix:
       env: DB=postgres
     - php: 5.4
       env: DB=sqlite3
+    - php: 5.4
+      env: DB=mysqli;SLOWTESTS=1
     - php: 5.5
       env: DB=mysqli
     - php: 5.6
@@ -41,6 +43,7 @@ script:
   - travis/check-sami-parse-errors.sh $DB $TRAVIS_PHP_VERSION
   - travis/check-image-icc-profiles.sh $DB $TRAVIS_PHP_VERSION
   - travis/check-executable-files.sh $DB $TRAVIS_PHP_VERSION ./
-  - phpBB/vendor/bin/phpunit --configuration travis/phpunit-$DB-travis.xml
+  - sh -c "if [ '$SLOWTESTS' != '1' ]; then phpBB/vendor/bin/phpunit --configuration travis/phpunit-$DB-travis.xml; fi"
+  - sh -c "if [ '$SLOWTESTS' = '1' ]; then phpBB/vendor/bin/phpunit --configuration travis/phpunit-$DB-travis.xml --group slow; fi"
   - sh -c "if [ '$TRAVIS_PHP_VERSION' = '5.3.3' -a '$DB' = 'mysqli' -a '$TRAVIS_PULL_REQUEST' != 'false' ]; then git-tools/commit-msg-hook-range.sh origin/$TRAVIS_BRANCH..FETCH_HEAD; fi"