diff --git a/protected/java/src/org/broadinstitute/sting/gatk/walkers/compression/reducereads/SingleSampleCompressor.java b/protected/java/src/org/broadinstitute/sting/gatk/walkers/compression/reducereads/SingleSampleCompressor.java
index 0edcb22e1..e9ad88c03 100644
--- a/protected/java/src/org/broadinstitute/sting/gatk/walkers/compression/reducereads/SingleSampleCompressor.java
+++ b/protected/java/src/org/broadinstitute/sting/gatk/walkers/compression/reducereads/SingleSampleCompressor.java
@@ -4,6 +4,7 @@ import org.broadinstitute.sting.utils.collections.Pair;
 import org.broadinstitute.sting.utils.sam.AlignmentStartWithNoTiesComparator;
 import org.broadinstitute.sting.utils.sam.GATKSAMRecord;
 
+import java.util.Collections;
 import java.util.Set;
 import java.util.TreeSet;