diff --git a/contracts/FixedRateRewardsSource.sol b/contracts/FixedRateRewardsSource.sol
index 1fb97db5..30f52139 100644
--- a/contracts/FixedRateRewardsSource.sol
+++ b/contracts/FixedRateRewardsSource.sol
@@ -89,9 +89,12 @@ contract FixedRateRewardsSource is Governable, Initializable {
     /// @return rewardAmount Amount of reward that'll be distributed if collected now
     function previewRewards() public view returns (uint256 rewardAmount) {
         RewardConfig memory _config = rewardConfig;
-
+        
+        if (_config.lastCollect == 0) {
+            return 0;
+        }
+        
         rewardAmount = (block.timestamp - _config.lastCollect) * _config.rewardsPerSecond;
-
         uint256 balance = IERC20(rewardToken).balanceOf(address(this));
         if (rewardAmount > balance) {
             rewardAmount = balance;