diff --git a/apps/web/src/components/nav/AddPlayerButton.tsx b/apps/web/src/components/nav/AddPlayerButton.tsx
new file mode 100644
index 00000000..6545ed0f
--- /dev/null
+++ b/apps/web/src/components/nav/AddPlayerButton.tsx
@@ -0,0 +1,155 @@
+import React from 'react'
+
+interface Player {
+  id: number
+  name: string
+  emoji: string
+}
+
+interface AddPlayerButtonProps {
+  inactivePlayers: Player[]
+  shouldEmphasize: boolean
+  onAddPlayer: (playerId: number) => void
+}
+
+export function AddPlayerButton({ inactivePlayers, shouldEmphasize, onAddPlayer }: AddPlayerButtonProps) {
+  const [showPopover, setShowPopover] = React.useState(false)
+  const popoverRef = React.useRef<HTMLDivElement>(null)
+
+  // Close popover when clicking outside
+  React.useEffect(() => {
+    const handleClickOutside = (event: MouseEvent) => {
+      if (popoverRef.current && !popoverRef.current.contains(event.target as Node)) {
+        setShowPopover(false)
+      }
+    }
+
+    if (showPopover) {
+      document.addEventListener('mousedown', handleClickOutside)
+      return () => document.removeEventListener('mousedown', handleClickOutside)
+    }
+  }, [showPopover])
+
+  const handleAddPlayerClick = (playerId: number) => {
+    onAddPlayer(playerId)
+    setShowPopover(false)
+  }
+
+  if (!shouldEmphasize || inactivePlayers.length === 0) {
+    return null
+  }
+
+  return (
+    <div style={{ position: 'relative' }} ref={popoverRef}>
+      <button
+        onClick={() => setShowPopover(!showPopover)}
+        style={{
+          fontSize: shouldEmphasize ? '32px' : '16px',
+          width: shouldEmphasize ? '48px' : '24px',
+          height: shouldEmphasize ? '48px' : '24px',
+          borderRadius: '50%',
+          border: '2px solid #10b981',
+          background: showPopover ? '#10b981' : 'rgba(16, 185, 129, 0.1)',
+          color: showPopover ? 'white' : '#10b981',
+          display: 'flex',
+          alignItems: 'center',
+          justifyContent: 'center',
+          cursor: 'pointer',
+          transition: 'all 0.3s ease',
+          padding: 0,
+          lineHeight: 1,
+          fontWeight: 'bold',
+          boxShadow: showPopover ? '0 4px 12px rgba(16, 185, 129, 0.4)' : 'none'
+        }}
+        onMouseEnter={(e) => {
+          if (!showPopover) {
+            e.currentTarget.style.background = '#10b981'
+            e.currentTarget.style.color = 'white'
+            e.currentTarget.style.transform = 'scale(1.1)'
+          }
+        }}
+        onMouseLeave={(e) => {
+          if (!showPopover) {
+            e.currentTarget.style.background = 'rgba(16, 185, 129, 0.1)'
+            e.currentTarget.style.color = '#10b981'
+            e.currentTarget.style.transform = 'scale(1)'
+          }
+        }}
+        title="Add player"
+      >
+        +
+      </button>
+
+      {/* Add Player Popover */}
+      {showPopover && (
+        <div
+          style={{
+            position: 'absolute',
+            top: 'calc(100% + 12px)',
+            right: 0,
+            background: 'white',
+            borderRadius: '12px',
+            boxShadow: '0 10px 40px rgba(0, 0, 0, 0.2)',
+            border: '2px solid #e5e7eb',
+            padding: '12px',
+            minWidth: '200px',
+            zIndex: 1000,
+            animation: 'fadeIn 0.2s ease'
+          }}
+        >
+          <div style={{
+            fontSize: '14px',
+            fontWeight: 'bold',
+            color: '#374151',
+            marginBottom: '8px',
+            paddingBottom: '8px',
+            borderBottom: '1px solid #e5e7eb'
+          }}>
+            Add Player
+          </div>
+          <div style={{
+            display: 'flex',
+            flexDirection: 'column',
+            gap: '4px'
+          }}>
+            {inactivePlayers.map(player => (
+              <button
+                key={player.id}
+                onClick={() => handleAddPlayerClick(player.id)}
+                style={{
+                  display: 'flex',
+                  alignItems: 'center',
+                  gap: '12px',
+                  padding: '8px 12px',
+                  background: 'transparent',
+                  border: 'none',
+                  borderRadius: '8px',
+                  cursor: 'pointer',
+                  transition: 'all 0.2s ease',
+                  textAlign: 'left'
+                }}
+                onMouseEnter={(e) => {
+                  e.currentTarget.style.background = '#f3f4f6'
+                }}
+                onMouseLeave={(e) => {
+                  e.currentTarget.style.background = 'transparent'
+                }}
+              >
+                <span style={{ fontSize: '24px', lineHeight: 1 }}>
+                  {player.emoji}
+                </span>
+                <span style={{
+                  fontSize: '14px',
+                  fontWeight: '500',
+                  color: '#1f2937'
+                }}>
+                  {player.name}
+                </span>
+              </button>
+            ))}
+          </div>
+        </div>
+      )}
+    </div>
+  )
+}
\ No newline at end of file