diff --git a/plugins/package-managers/cargo/src/main/kotlin/Cargo.kt b/plugins/package-managers/cargo/src/main/kotlin/Cargo.kt
index b4dd4a963b134..e1fe6bc0bfae0 100644
--- a/plugins/package-managers/cargo/src/main/kotlin/Cargo.kt
+++ b/plugins/package-managers/cargo/src/main/kotlin/Cargo.kt
@@ -164,10 +164,6 @@ class Cargo(
     }
 
     override fun resolveDependencies(definitionFile: File, labels: Map<String, String>): List<ProjectAnalyzerResult> {
-        // Get the project name and version. If one of them is missing return null, because this is a workspace
-        // definition file that does not contain a project.
-        val pkgDefinition = definitionFile.reader().use { toml.decodeFromNativeReader<CargoManifest>(it) }
-
         val workingDir = definitionFile.parentFile
         val metadataProcess = run(workingDir, "metadata", "--format-version=1")
         val metadata = json.decodeFromString<CargoMetadata>(metadataProcess.stdout)
@@ -178,8 +174,8 @@ class Cargo(
             { parsePackage(it, hashes) }
         )
 
-        val projectId = metadata.workspaceMembers.single {
-            it.startsWith("${pkgDefinition.pkg.name} ${pkgDefinition.pkg.version}")
+        val projectId = requireNotNull(metadata.resolve.root) {
+            "Virtual workspaces are not supported."
         }
 
         val projectNode = metadata.packages.single { it.id == projectId }
@@ -190,8 +186,7 @@ class Cargo(
 
             val transitiveDependencies = directDependencies
                 .mapNotNull { dependency ->
-                    val version =
-                        getResolvedVersion(pkgDefinition.pkg.name, pkgDefinition.pkg.version, dependency.name, metadata)
+                    val version = getResolvedVersion(projectNode.name, projectNode.version, dependency.name, metadata)
                     version?.let { Pair(dependency.name, it) }
                 }
                 .mapTo(mutableSetOf()) {
@@ -207,12 +202,10 @@ class Cargo(
             getTransitiveDependencies(groupedDependencies["build"], "build-dependencies")
         )
 
-        val projectPkg = packages.values.single { pkg ->
-            pkg.id.name == pkgDefinition.pkg.name && pkg.id.version == pkgDefinition.pkg.version
-        }.let { it.copy(id = it.id.copy(type = managerName)) }
+        val projectPkg = packages.getValue(projectId).let { it.copy(id = it.id.copy(type = managerName)) }
 
-        val homepageUrl = pkgDefinition.pkg.homepage.orEmpty()
-        val authors = pkgDefinition.pkg.authors.mapNotNullTo(mutableSetOf(), ::parseAuthorString)
+        val homepageUrl = projectNode.homepage.orEmpty()
+        val authors = projectNode.authors.mapNotNullTo(mutableSetOf(), ::parseAuthorString)
 
         val project = Project(
             id = projectPkg.id,
diff --git a/plugins/package-managers/cargo/src/main/kotlin/CargoManifest.kt b/plugins/package-managers/cargo/src/main/kotlin/CargoManifest.kt
deleted file mode 100644
index 249fa79f315db..0000000000000
--- a/plugins/package-managers/cargo/src/main/kotlin/CargoManifest.kt
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * Copyright (C) 2023 The ORT Project Authors (see <https://github.com/oss-review-toolkit/ort/blob/main/NOTICE>)
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- * SPDX-License-Identifier: Apache-2.0
- * License-Filename: LICENSE
- */
-
-package org.ossreviewtoolkit.plugins.packagemanagers.cargo
-
-import kotlinx.serialization.SerialName
-import kotlinx.serialization.Serializable
-
-/**
- * See https://doc.rust-lang.org/cargo/reference/manifest.html.
- */
-@Serializable
-internal data class CargoManifest(
-    @SerialName("package")
-    val pkg: Package
-) {
-    /**
-     * See https://doc.rust-lang.org/cargo/reference/manifest.html#the-package-section.
-     */
-    @Serializable
-    data class Package(
-        val name: String,
-        val version: String,
-        val authors: List<String> = emptyList(),
-        val homepage: String? = null
-    )
-}