diff --git a/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelPhase2DigiToCluster.cc b/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelPhase2DigiToCluster.cc
index ce337a848d952..f4a4b34a9b7f3 100644
--- a/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelPhase2DigiToCluster.cc
+++ b/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelPhase2DigiToCluster.cc
@@ -141,8 +141,10 @@ namespace ALPAKA_ACCELERATOR_NAMESPACE {
     }
     digis_d_ = SiPixelDigisSoACollection(iEvent.queue(), nDigis_);
 
-    if (nDigis_ == 0)
+    if (nDigis_ == 0) {
+      algo_.zeroInitializePhase2Clusters(iEvent.queue());
       return;
+    }
 
     SiPixelDigisHost digis_h(iEvent.queue(), nDigis_);
 
@@ -170,14 +172,11 @@ namespace ALPAKA_ACCELERATOR_NAMESPACE {
   }
 
   void SiPixelPhase2DigiToCluster::produce(device::Event& iEvent, device::EventSetup const& iSetup) {
-    if (nDigis_ == 0) {
-      iEvent.emplace(digiPutToken_, std::move(*digis_d_));
-      iEvent.emplace(clusterPutToken_, iEvent.queue(), pixelTopology::Phase2::numberOfModules);
-    } else {
+    if (nDigis_ != 0)
       digis_d_->setNModules(algo_.nModules());
-      iEvent.emplace(digiPutToken_, std::move(*digis_d_));
-      iEvent.emplace(clusterPutToken_, algo_.getClusters());
-    }
+
+    iEvent.emplace(digiPutToken_, std::move(*digis_d_));
+    iEvent.emplace(clusterPutToken_, algo_.getClusters());
     digis_d_.reset();
   }
 
diff --git a/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.dev.cc b/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.dev.cc
index 810f2e8a168cd..2a7a15c51e7af 100644
--- a/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.dev.cc
+++ b/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.dev.cc
@@ -771,6 +771,19 @@ namespace ALPAKA_ACCELERATOR_NAMESPACE {
 #endif
     }  //
 
+    // Function to zero-initialize the clusters
+    template <typename TrackerTraits>
+    void SiPixelRawToClusterKernel<TrackerTraits>::zeroInitializePhase2Clusters(Queue &queue) {
+      constexpr int numberOfModules = pixelTopology::Phase2::numberOfModules;
+      clusters_d = SiPixelClustersSoACollection(queue, numberOfModules);
+      clusters_d->zeroInitialise(queue);
+      // set moduleStartFirstElement, moduleStartLastElement and bpix2ClusterStart on the host to zero
+      // these changes are later propagated to the device portable collection during getDigis() and getClusters()
+      nModules_Clusters_h[0] = 0;
+      nModules_Clusters_h[1] = 0;
+      nModules_Clusters_h[2] = 0;
+    }
+
     template class SiPixelRawToClusterKernel<pixelTopology::Phase1>;
     template class SiPixelRawToClusterKernel<pixelTopology::Phase2>;
     template class SiPixelRawToClusterKernel<pixelTopology::HIonPhase1>;
diff --git a/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.h b/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.h
index cd50ff4eca8e7..33be7ba434016 100644
--- a/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.h
+++ b/RecoLocalTracker/SiPixelClusterizer/plugins/alpaka/SiPixelRawToClusterKernel.h
@@ -177,6 +177,8 @@ namespace ALPAKA_ACCELERATOR_NAMESPACE {
                                    const uint32_t numDigis,
                                    const uint32_t offsetBPIX2);
 
+      void zeroInitializePhase2Clusters(Queue& queue);
+
       SiPixelDigisSoACollection getDigis() {
         digis_d->setNModules(nModules_Clusters_h[0]);
         return std::move(*digis_d);