diff --git a/src/hash/poseidon.rs b/src/hash/poseidon.rs
index d5cb13a0..5bd40eab 100644
--- a/src/hash/poseidon.rs
+++ b/src/hash/poseidon.rs
@@ -519,6 +519,12 @@ impl Poseidon<8> for CrandallField {
     fn mds_layer(state_: &[CrandallField; 8]) -> [CrandallField; 8] {
         crate::hash::poseidon_neon::crandall_poseidon8_mds_neon(*state_)
     }
+
+    #[cfg(target_feature="avx2")]
+    #[inline(always)]
+    fn sbox_layer(state: &mut [Self; 8]) {
+        crate::hash::poseidon_avx2::crandall_poseidon_sbox_avx2::<2>(state);
+    }
 }
 
 #[rustfmt::skip]
@@ -744,6 +750,12 @@ impl Poseidon<12> for CrandallField {
     fn mds_layer(state_: &[CrandallField; 12]) -> [CrandallField; 12] {
         crate::hash::poseidon_neon::crandall_poseidon12_mds_neon(*state_)
     }
+
+    #[cfg(target_feature="avx2")]
+    #[inline(always)]
+    fn sbox_layer(state: &mut [Self; 12]) {
+        crate::hash::poseidon_avx2::crandall_poseidon_sbox_avx2::<3>(state);
+    }
 }
 
 #[cfg(test)]
diff --git a/src/hash/poseidon_avx2.rs b/src/hash/poseidon_avx2.rs
index 643317f8..cc4a3d1d 100644
--- a/src/hash/poseidon_avx2.rs
+++ b/src/hash/poseidon_avx2.rs
@@ -220,3 +220,28 @@ pub unsafe fn crandall_poseidon_const_avx2<const PACKED_WIDTH: usize>(
         packed_state[i] = packed_state[i].add_canonical_u64(packed_round_constants[i]);
     }
 }
+
+#[inline(always)]
+pub fn crandall_poseidon_sbox_avx2<const PACKED_WIDTH: usize>(
+    state: &mut [CrandallField; 4 * PACKED_WIDTH],
+) {
+    // This function is manually interleaved to maximize instruction-level parallelism.
+
+    let packed_state = PackedCrandallAVX2::pack_slice_mut(state);
+
+    let mut x2 = [PackedCrandallAVX2::zero(); PACKED_WIDTH];
+    for i in 0..PACKED_WIDTH {
+        x2[i] = packed_state[i].square();
+    }
+
+    let mut x3 = [PackedCrandallAVX2::zero(); PACKED_WIDTH];
+    let mut x4 = [PackedCrandallAVX2::zero(); PACKED_WIDTH];
+    for i in 0..PACKED_WIDTH {
+        x3[i] = packed_state[i] * x2[i];
+        x4[i] = x2[i].square();
+    }
+
+    for i in 0..PACKED_WIDTH {
+        packed_state[i] = x3[i] * x4[i];
+    }
+}