diff --git a/tests/sparse-pads.test.ts b/tests/sparse-pads.test.ts
new file mode 100644
index 0000000..045249e
--- /dev/null
+++ b/tests/sparse-pads.test.ts
@@ -0,0 +1,100 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { collectPads } from '../src/lib/parsers';
+import abletonTransformer from '../src/lib/transformers/ableton';
+import dawProjectTransformer from '../src/lib/transformers/dawProject';
+import midiTransformer from '../src/lib/transformers/midi';
+import reaperTransformer from '../src/lib/transformers/reaper';
+import { TarFile } from '../src/lib/untar';
+import {
+  EffectType,
+  FaderParam,
+  Group,
+  GroupFaderParam,
+  ProjectRawData,
+} from '../src/types/types';
+import { findPad } from '../src/lib/utils';
+
+function faderParams(): GroupFaderParam {
+  return Object.fromEntries(
+    (['a', 'b', 'c', 'd'] as Group[]).map((group) => [
+      group,
+      Object.fromEntries(Array.from({ length: 12 }, (_, parameter) => [parameter, -1])),
+    ]),
+  ) as GroupFaderParam;
+}
+
+function sparseProject(): ProjectRawData {
+  const rawPad = new Uint8Array(27);
+  rawPad[1] = 202;
+  rawPad[16] = 100;
+  rawPad[20] = 255;
+  rawPad[24] = 60;
+  const pads = collectPads([new TarFile('pads/a/p02', rawPad.length, rawPad)], []);
+  const params = faderParams();
+
+  return {
+    pads,
+    groupPatterns: [],
+    scenes: [
+      {
+        number: 1,
+        name: '01',
+        patternNumbers: { a: 0, b: 0, c: 0, d: 0 },
+        timeSignature: { numerator: 4, denominator: 4 },
+        patterns: [],
+        patternEvents: {},
+      },
+    ],
+    songPositions: [],
+    settings: {
+      bpm: 120,
+      scale: 0,
+      rootNote: 0,
+      groupFaderParams: params,
+      faderAssignment: {
+        a: FaderParam.LVL,
+        b: FaderParam.LVL,
+        c: FaderParam.LVL,
+        d: FaderParam.LVL,
+      },
+      rawData: new Uint8Array(),
+    },
+    effects: {
+      rawData: new Uint8Array(),
+      effectType: EffectType.Off,
+      param1: 0,
+      param2: 0,
+    },
+    sounds: [],
+    projectFile: {} as File,
+    scenesSettings: { timeSignature: { numerator: 4, denominator: 4 } },
+  };
+}
+
+test('keeps physical p02 on zero-based pattern source 1 when p01 is omitted', () => {
+  const data = sparseProject();
+  const physicalPad = data.pads.a[0];
+
+  assert.equal(physicalPad.pad, 2);
+  assert.equal(findPad('a0', data.pads), undefined);
+  assert.equal(findPad('a1', data.pads), physicalPad);
+
+  const params = { exportAllPadsWithSamples: true, keepUnusedPatterns: false };
+  assert.deepEqual(
+    abletonTransformer(data, params).tracks.map((track) => track.padCode),
+    ['a1'],
+  );
+  assert.deepEqual(
+    midiTransformer(data, params).tracks.map((track) => track.padCode),
+    ['a1'],
+  );
+  assert.deepEqual(
+    reaperTransformer(data, params).tracks.map((track) => track.padCode),
+    ['a1'],
+  );
+  assert.deepEqual(
+    dawProjectTransformer(data, params).tracks.map((track) => track.padCode),
+    ['a1'],
+  );
+});