diff --git a/cmake/std/atdm/waterman/tweaks/CUDA-9.2-DEBUG-CUDA-POWER9-VOLTA70.cmake b/cmake/std/atdm/waterman/tweaks/CUDA-9.2-DEBUG-CUDA-POWER9-VOLTA70.cmake
index fac875fb35ee..fcab6639fc0f 100644
--- a/cmake/std/atdm/waterman/tweaks/CUDA-9.2-DEBUG-CUDA-POWER9-VOLTA70.cmake
+++ b/cmake/std/atdm/waterman/tweaks/CUDA-9.2-DEBUG-CUDA-POWER9-VOLTA70.cmake
@@ -4,5 +4,10 @@ ATDM_SET_ENABLE(TeuchosNumerics_LAPACK_test_MPI_1_DISABLE ON)
 #disable from issue #2466
 ATDM_SET_ENABLE(Belos_Tpetra_PseudoBlockCG_hb_test_MPI_4_DISABLE ON)
 
+# Disable some unit tests that run too slow in this DEBUG build (#2827)
+ATDM_SET_CACHE(KokkosKernels_sparse_serial_MPI_1_EXTRA_ARGS
+  "--gtest_filter=-serial.sparse_block_gauss_seidel_double_int_int_TestExecSpace:serial.sparse_block_gauss_seidel_double_int_size_t_TestExecSpace:serial.sparse_trsv_mv_double_int_int_LayoutLeft_TestExecSpace"
+  CACHE STRING )
+
 INCLUDE("${CMAKE_CURRENT_LIST_DIR}/CUDA_COMMON_TWEAKS.cmake")
 INCLUDE("${CMAKE_CURRENT_LIST_DIR}/ALL_COMMON_TWEAKS.cmake")
diff --git a/cmake/std/atdm/waterman/tweaks/GNU-DEBUG-OPENMP-POWER9.cmake b/cmake/std/atdm/waterman/tweaks/GNU-DEBUG-OPENMP-POWER9.cmake
index 5660992ded59..7034a7bb51df 100644
--- a/cmake/std/atdm/waterman/tweaks/GNU-DEBUG-OPENMP-POWER9.cmake
+++ b/cmake/std/atdm/waterman/tweaks/GNU-DEBUG-OPENMP-POWER9.cmake
@@ -4,6 +4,11 @@ ATDM_SET_ENABLE(TeuchosNumerics_LAPACK_test_MPI_1_DISABLE ON)
 #disable from issue #2466
 ATDM_SET_ENABLE(Belos_Tpetra_PseudoBlockCG_hb_test_MPI_4_DISABLE ON)
 
+# Disable some unit tests that run too slow in this DEBUG build (#2827)
+ATDM_SET_CACHE(KokkosKernels_sparse_serial_MPI_1_EXTRA_ARGS
+  "--gtest_filter=-serial.sparse_block_gauss_seidel_double_int_int_TestExecSpace:serial.sparse_block_gauss_seidel_double_int_size_t_TestExecSpace:serial.sparse_trsv_mv_double_int_int_LayoutLeft_TestExecSpace"
+  CACHE STRING )
+
 #disable failing test as in #3173
 ATDM_SET_ENABLE(KokkosKernels_sparse_openmp_MPI_1_DISABLE ON)