diff --git a/open-sse/services/autoCombo/__tests__/speedRanking.test.ts b/open-sse/services/autoCombo/__tests__/speedRanking.test.ts
index 1599e36b82..e3a4ad85f2 100644
--- a/open-sse/services/autoCombo/__tests__/speedRanking.test.ts
+++ b/open-sse/services/autoCombo/__tests__/speedRanking.test.ts
@@ -165,15 +165,34 @@ describe("rankBySpeed — factor breakdown", () => {
   });
 
   it("falls back to 0.5 per missing metric so new providers are not crushed", () => {
-    const ranked = rankBySpeed([candidate({ provider: "fresh", model: "m" })]);
+    const ranked = rankBySpeed([
+      candidate({
+        provider: "fresh",
+        model: "m",
+        p95LatencyMs: undefined,
+        latencyStdDev: undefined,
+      }),
+    ]);
     expect(ranked).toHaveLength(1);
     // No telemetry at all → weighted sum lands near 0.5 with reliability multiplier 1
     expect(ranked[0].factors.reliability).toBe(1);
     expect(ranked[0].factors.health).toBe(1);
     expect(ranked[0].factors.ttft).toBe(0.5);
-    expect(ranked[0].factors.tps).toBe(0.5);
-  });
-});
+    expect(ranked[0].factors.tps).toBe(0.5);
+  });
+
+  it("uses p95 latency when TTFT and E2E telemetry are unavailable", () => {
+    const ranked = rankBySpeed([
+      candidate({ provider: "slow-tail", model: "m", p95LatencyMs: 4000 }),
+      candidate({ provider: "fast-tail", model: "m", p95LatencyMs: 1000 }),
+    ]);
+    const fast = ranked.find((entry) => entry.provider === "fast-tail");
+    const slow = ranked.find((entry) => entry.provider === "slow-tail");
+
+    expect(fast?.factors.ttft).toBeGreaterThan(slow?.factors.ttft ?? 1);
+    expect(fast?.factors.e2e).toBeGreaterThan(slow?.factors.e2e ?? 1);
+  });
+});
 
 describe("rankBySpeed — weight overrides", () => {
   it("respects caller weight overrides (e.g. heavy TTFT bias)", () => {
@@ -223,4 +242,4 @@ describe("pickFastest", () => {
     const winner = pickFastest([slow, fast]);
     expect(winner?.provider).toBe("fast");
   });
-});
\ No newline at end of file
+});
diff --git a/open-sse/services/autoCombo/speedRanking.ts b/open-sse/services/autoCombo/speedRanking.ts
index 514420a5a0..a3d7d81027 100644
--- a/open-sse/services/autoCombo/speedRanking.ts
+++ b/open-sse/services/autoCombo/speedRanking.ts
@@ -211,9 +211,15 @@ function speedFactorsFor(
   failureRate: number
 ): SpeedFactors {
   return {
-    ttft: lowerIsBetter(positiveFinite(candidate.avgTtftMs), maxima.ttft),
+    ttft: lowerIsBetter(
+      positiveFinite(candidate.avgTtftMs) ?? positiveFinite(candidate.p95LatencyMs),
+      maxima.ttft
+    ),
     tps: higherIsBetter(positiveFinite(candidate.avgTokensPerSecond), maxima.tps),
-    e2e: lowerIsBetter(positiveFinite(candidate.avgE2ELatencyMs), maxima.e2e),
+    e2e: lowerIsBetter(
+      positiveFinite(candidate.avgE2ELatencyMs) ?? positiveFinite(candidate.p95LatencyMs),
+      maxima.e2e
+    ),
     p95: lowerIsBetter(positiveFinite(candidate.p95LatencyMs), maxima.p95),
     health: healthScoreFor(candidate.circuitBreakerState),
     reliability: clamp01(1 - failureRate),